Maybe he pulled a Crusher and left for Starfleet Medical. Except this time when he came crawling back to the Enterprise the new CMO didn't just meekly give up the job like Pulaski did.
As an Asian I have very mixed feelings about Kyle being Asian and the implication this is the TOS Kyle.
@Nerys Myk said in another post that this is just a new Asian character also named Kyle, but unless it's his first name Kyle isn't an Asian surname that I'm aware of and there's no point in naming him as such honestly unless to basically say he's the TOS Kyle. I want better Asian representation in my shows but not at the expense of contradicting the previous established canon of another character.