Below is my postgresql materialize view code

-- public.reporting_user_activity_contents source

CREATE MATERIALIZED VIEW public.reporting_user_activity_contents
TABLESPACE pg_default
AS WITH sub_q AS (
         SELECT u.id AS user_id,
            t.id AS tenant_id,
            t.global_tenant_id,
            m.id AS content_id,
            m.title AS content_title,
            um.id AS user_mission_id,
            mk.id AS content_kind_id,
            mk.kind AS content_kind,
            gp.path_id,
            gp.group_id AS assigned_through_group_id,
            COALESCE(ugpr.hidden, false) AS hidden,
                CASE
                    WHEN uv.created_at IS NOT NULL THEN uv.created_at
                    WHEN uv.created_at IS NULL THEN ugpr.viewed_at
                    ELSE NULL::timestamp without time zone
                END AS first_viewed_at,
                CASE
                    WHEN um.completed_at IS NOT NULL THEN um.completed_at
                    WHEN um.completed_at IS NULL THEN ugpr.completed_at
                    ELSE NULL::timestamp without time zone
                END AS first_completed_at,
                CASE
                    WHEN ugpr.discussed_at IS NOT NULL THEN ugpr.discussed_at
                    ELSE NULL::timestamp without time zone
                END AS first_discussed_at,
                CASE
                    WHEN gpr.discussable THEN gpr.discussable
                    ELSE false
                END AS discussible,
            ( SELECT to_jsonb(array_to_json(array_agg(row_to_json(t_1.*)))) AS to_jsonb
                   FROM ( SELECT tags.id,
                            tags.name,
                            tags.taggings_count
                           FROM tags
                             JOIN taggings ON tags.id = taggings.tag_id
                          WHERE taggings.taggable_id = m.id AND taggings.taggable_type::text = 'Mission'::text AND (taggings.context::text = ANY (ARRAY['tags'::character varying::text, 'skills'::character varying::text, 'skill_groups'::character varying::text, 'levels'::character varying::text]))) t_1) AS tags
           FROM missions m
             JOIN user_missions um ON um.mission_id = m.id AND um.assigned_through_type::text = 'Space'::text
             LEFT JOIN user_views uv ON uv.viewable_id = m.id AND uv.user_id = um.user_id AND uv.viewable_type::text = 'Mission'::text
             JOIN mission_kinds mk ON mk.id = m.mission_kind_id
             JOIN users u ON u.id = um.user_id
             JOIN tenants t ON u.tenant_id = t.id
             LEFT JOIN group_path_resources gpr ON gpr.id = uv.assigned_through_id AND uv.assigned_through_type::text = 'GroupPathResource'::text AND gpr.resourceable_type::text = 'Mission'::text AND gpr.resourceable_id = um.mission_id
             LEFT JOIN group_path_sections gps ON gps.id = gpr.group_path_section_id
             LEFT JOIN group_paths gp ON gp.id = gps.group_path_id
             LEFT JOIN user_group_path_resources ugpr ON ugpr.group_path_resource_id = gpr.id AND ugpr.resourceable_id = um.id AND ugpr.resourceable_type::text = 'UserMission'::text
        )
 SELECT sub_q.user_id,
    sub_q.tenant_id,
    sub_q.global_tenant_id,
    sub_q.content_id,
    sub_q.content_title,
    sub_q.user_mission_id,
    sub_q.content_kind_id,
    sub_q.content_kind,
    sub_q.path_id,
    sub_q.assigned_through_group_id,
    sub_q.discussible,
    sub_q.tags,
    min(sub_q.first_viewed_at) AS first_viewed_at,
    min(sub_q.first_completed_at) AS first_completed_at,
    min(sub_q.first_discussed_at) AS first_discussed_at,
    bool_and(sub_q.hidden) AS hidden
   FROM sub_q
  WHERE sub_q.tenant_id IS NOT NULL
  GROUP BY sub_q.user_id, sub_q.tenant_id, sub_q.global_tenant_id, sub_q.content_id, sub_q.content_title, sub_q.user_mission_id, sub_q.content_kind_id, sub_q.content_kind, sub_q.path_id, sub_q.assigned_through_group_id, sub_q.discussible, sub_q.tags
WITH DATA;

— View indexes:

CREATE INDEX idx_u_t_gt_c_atg ON public.reporting_user_activity_contents USING btree (content_id, user_mission_id, user_id, tenant_id, global_tenant_id, assigned_through_group_id, path_id);
CREATE INDEX ruac_atg_p ON public.reporting_user_activity_contents USING btree (assigned_through_group_id, path_id);
CREATE INDEX ruac_t_gt ON public.reporting_user_activity_contents USING btree (tenant_id, global_tenant_id);
CREATE INDEX ruac_u_atg ON public.reporting_user_activity_contents USING btree (user_id, assigned_through_group_id);

To reduce the execution time , I changed the join structure and removed the filter column casting & also removed the where clause from outer query and added in cte ,
what are the changes required in this code to reduce execution time upto 50 seconds

explain analyze
WITH sub_q AS (
         SELECT u.id AS user_id,
            t.id AS tenant_id,
            t.global_tenant_id,
            m.id AS content_id,
            m.title AS content_title,
            um.id AS user_mission_id,
            mk.id AS content_kind_id,
            mk.kind AS content_kind,
            gp.path_id,
            gp.group_id AS assigned_through_group_id,
            COALESCE(ugpr.hidden, false) AS hidden,
               /* CASE
                    WHEN uv.created_at IS NOT NULL THEN uv.created_at
                    WHEN uv.created_at IS NULL THEN ugpr.viewed_at
                    ELSE NULL::timestamp without time zone
                END AS first_viewed_at,
                */
                COALESCE(uv.created_at, ugpr.viewed_at) AS first_viewed_at,
              /*  
                CASE
                    WHEN um.completed_at IS NOT NULL THEN um.completed_at
                    WHEN um.completed_at IS NULL THEN ugpr.completed_at
                    ELSE NULL::timestamp without time zone
                END AS first_completed_at,
                */
                COALESCE(um.completed_at, ugpr.completed_at) AS first_completed_at,
                /*CASE
                    WHEN ugpr.discussed_at IS NOT NULL THEN ugpr.discussed_at
                    ELSE NULL::timestamp without time zone
                END AS first_discussed_at,
                */
                ugpr.discussed_at AS first_discussed_at,
                /*CASE
                    WHEN gpr.discussable THEN gpr.discussable
                    ELSE false
                END AS discussible, */
                COALESCE(gpr.discussable, false) AS discussible,
            /*( SELECT to_jsonb(array_to_json(array_agg(row_to_json(t_1.*)))) AS to_jsonb
              FROM 
                    ( SELECT tags.id,
                            tags.name,
                            tags.taggings_count
                      FROM tags
                      JOIN taggings ON tags.id = taggings.tag_id
                      WHERE taggings.taggable_id = m.id 
                      AND taggings.taggable_type::text = 'Mission'::text 
                      AND (taggings.context::text = ANY (ARRAY['tags'::character varying::text, 'skills'::character varying::text, 'skill_groups'::character varying::text, 'levels'::character varying::text]))
                    ) t_1
            ) AS tags*/
           (
                SELECT jsonb_agg(jsonb_build_object('id', tags.id, 'name', tags.name, 'taggings_count', tags.taggings_count))
                FROM taggings
                JOIN tags ON tags.id = taggings.tag_id
                WHERE taggings.taggable_id = m.id
                AND taggings.taggable_type = 'Mission'
                AND taggings.context = ANY (ARRAY['tags', 'skills', 'skill_groups', 'levels'])
            ) AS tags
          /*  FROM missions m
            JOIN mission_kinds mk ON m.mission_kind_id = mk.id
            JOIN user_missions um ON um.mission_id = m.id AND um.assigned_through_type = 'Space'
            JOIN users u ON um.user_id = u.id
            JOIN tenants t ON u.tenant_id = t.id
            LEFT JOIN user_views uv ON uv.viewable_id = m.id AND uv.user_id = um.user_id AND uv.viewable_type = 'Mission'
            LEFT JOIN group_path_resources gpr ON gpr.id = uv.assigned_through_id AND uv.assigned_through_type = 'GroupPathResource' AND gpr.resourceable_type = 'Mission' AND gpr.resourceable_id = um.mission_id
            LEFT JOIN group_path_sections gps ON gps.id = gpr.group_path_section_id
            LEFT JOIN group_paths gp ON gp.id = gps.group_path_id
            LEFT JOIN user_group_path_resources ugpr ON ugpr.group_path_resource_id = gpr.id AND ugpr.resourceable_id = um.id AND ugpr.resourceable_type = 'UserMission'
            WHERE t.id IS NOT NULL*/
            
            /*
            from mission_kinds mk
            join missions m  ON mk.id = m.mission_kind_id
            JOIN user_missions um ON um.mission_id = m.id AND um.assigned_through_type = 'Space'
            JOIN users u ON u.id = um.user_id
            JOIN tenants t ON u.tenant_id = t.id
            LEFT JOIN user_views uv ON uv.viewable_id = m.id AND uv.user_id = um.user_id AND uv.viewable_type = 'Mission'
            LEFT JOIN group_path_resources gpr ON gpr.id = uv.assigned_through_id AND uv.assigned_through_type= 'GroupPathResource' AND gpr.resourceable_type = 'Mission' AND gpr.resourceable_id = um.mission_id
            LEFT JOIN group_path_sections gps ON gps.id = gpr.group_path_section_id
            LEFT JOIN group_paths gp ON gp.id = gps.group_path_id
            LEFT JOIN user_group_path_resources ugpr ON ugpr.group_path_resource_id = gpr.id AND ugpr.resourceable_id = um.id AND ugpr.resourceable_type = 'UserMission'
            WHERE t.id IS NOT null
            */
            
            FROM tenants t
            JOIN users u ON u.tenant_id = t.id
            JOIN user_missions um ON um.user_id = u.id AND um.assigned_through_type = 'Space'
            JOIN missions m ON m.id = um.mission_id
            LEFT JOIN user_views uv ON uv.user_id = u.id AND uv.viewable_id = m.id AND uv.viewable_type = 'Mission'
            LEFT JOIN user_group_path_resources ugpr ON ugpr.resourceable_id = um.id AND ugpr.resourceable_type = 'UserMission'
            LEFT JOIN group_path_resources gpr ON gpr.id = uv.assigned_through_id AND uv.assigned_through_type = 'GroupPathResource' AND gpr.resourceable_type = 'Mission' AND gpr.resourceable_id = um.mission_id
            LEFT JOIN group_path_sections gps ON gps.id = gpr.group_path_section_id
            LEFT JOIN group_paths gp ON gp.id = gps.group_path_id
            LEFT JOIN mission_kinds mk ON mk.id = m.mission_kind_id
            WHERE t.id IS NOT NULL 

        )
 SELECT sub_q.user_id,
    sub_q.tenant_id,
    sub_q.global_tenant_id,
    sub_q.content_id,
    sub_q.content_title,
    sub_q.user_mission_id,
    sub_q.content_kind_id,
    sub_q.content_kind,
    sub_q.path_id,
    sub_q.assigned_through_group_id,
    sub_q.discussible,
    sub_q.tags,
    min(sub_q.first_viewed_at) AS first_viewed_at,
    min(sub_q.first_completed_at) AS first_completed_at,
    min(sub_q.first_discussed_at) AS first_discussed_at,
    bool_and(sub_q.hidden) AS hidden
   FROM sub_q
 --WHERE sub_q.tenant_id IS NOT NULL
  GROUP BY sub_q.user_id, sub_q.tenant_id, sub_q.global_tenant_id, sub_q.content_id, sub_q.content_title, 
           sub_q.user_mission_id, sub_q.content_kind_id, sub_q.content_kind, sub_q.path_id, sub_q.assigned_through_group_id, sub_q.discussible, sub_q.tags;

Explain plan is https://explain.depesz.com/s/C5vQ#stats