> Possible that people would schedule meetings over "Focus" time, but since they can't see calendar details, they don't. If they did, I'd push back. (It's easy to see: "This thing is due on Monday, and that's the time I have to work on it. If you don't like that, take it up to my manager." but more diplomatically. But I don't remember it being an issue.)
However, you're saying people straight scheduling over other people's meetings generally? The only times where that happens to me are either:
1) I'm really non-essential, and more invited as a courtesy in case I want to join, or
2) this is really, really important, and we will work together to sort the scheduling out, including manager if necessary.
Otherwise, what else can they expect than me saying "sorry, have another meeting already"?