The boarding pass won’t print (be generated) if you’re on the list. I don’t think the airline will know why, and there’s nothing they can do. It’s all CDC needing to clear it.
It’s for flights within the US as well.

I’m just wondering if clearing happens as it says no matter what communicable disease might put the person on the list - measles, TB, COVID, monkeypox, etc.

I’ll know from one person soon enough, but was hoping someone here might have had experience.