My understanding is that being able to hide Home pages predates Focus modes as it was the poor (and hard to discover) solution to what the Apps Library became (

My understanding is that being able to hide Home pages predates Focus modes as it was the poor (and hard to discover) solution to what the Apps Library became (for apps that you needed installed but didn't care to see all the time). But yes, Focus Modes definitely elevates it to another level when you've got Mode-specific pages.