Big, massive, complex apps with long histories, massive developer teams, and massive testing programs, are slow to change. Maybe all these features are easy to do for Office, as they have been easy with (some) other apps; and maybe no consequences or bugs will result from the changes. Maybe. Or maybe this really is something that needs to be done right, albeit slower than we’d like.
I give Microsoft credit here: they’re not waiting for the next big version, nor playing “wait and see.” I wonder how Adobe’s handling these features....
How do we know that work on these features isn’t partly done, and has long since been in progress? Yes, it’s amazing to think that changing one part of a software program could impact other parts, and that it could take months and months. But that is in fact the case sometimes. Is it the case here, or is the Mac BU just being slow and not caring? The latter might be true, I won’t deny--but I don’t think we have the evidence to accuse them yet.
Fullscreen is so simple to implement, it's stupid, they could have at the very least thrown that in. I don't know too much about autosave or versions though, but I know they're not hard either.