MongoDB: Should i do all crud operation using username or objectId or use username to find objectId and then use this id to do crud operation?

1> Using ObjectId is not convenient from end user perspective
await User.findByIdAndDelete({req.params.id});

2> Using username is more convenient from end user perspective
await User.findByIdAndDelete({req.params.id})

3>Provide API endpoints or methods that allow querying and updating users using usernames. Internally, resolve these usernames to ObjectIDs for database operations.

async function getChatByUsername(username) {
    const user = await User.findOne({ username: username });
    if (user) {
        return await Chat.find({ userId: user._id });
    }
    throw new Error('User not found');
}

logically all are correct but which one is optimised?

just want to know which one is more efficient