You will quickly learn that players don't want "what's in Xanathars" or "what's in Tasha's" - they want 'Whatever you've disallowed."
No-one will want to play genasi, right up to the point where you remove them from the allowed list, and then three players will complain, 'But I wanted to be a genasi!"
PHB only is fine. I've run games that were just PHB and SCAG when other books were available, and apart from constant complaining (sheesh, every single session, "you should let us play Z" arrgghh) the game ran fine.
I would suggest looking at the Revised Ranger though, as the PHB ranger is a little bit crap.
I'm contemplating my next D&D 5E game being PHB-only, no-optional-rules. Just to see what its like.