I am trying to get my mental picture right about how Event Grid System Topic works.

Is it “correct” to say that when you create a system topic, then that the topic may handle ALL the events from the selected Azure Service?

And that it is then up to the individual subscriptions on that topic, to filter out what events you want to receive?

I understand the system topics are managed by Azure and what’s inside is “hidden” but I want to know if my mental model and understanding of them is correct or not?

Or does the system topic only handles the union of all the events that the subscriptions are asking for?