People who definitely make all NBA teams over Hayward:
Lebron
Durant
Harden
Westbrook
Curry
Kawhi
Lowry
Butler
Kyrie
Giannis
Davis (assuming that his stats don't go way down now that he's next to Boogie)
Boogie (ditto)
Players that probably make it over him:
IT
John Wall
Derozan
Jokic
Towns
Feel free to dispute some of those, but that's 17 guys. I just can't see Hayward making it unless he picks it way up or some people drop off.
They award All-NBA by position (albeit loosely). Hayward presumably is a forward, so he needs to be one of the top 6. The nice thing about the Boogie trade from this respect is that Anthony Davis should solidify himself as a forward instead of a center for purposes of this award. At the same time, Jimmy Butler could be shifted to guard.
Also, I know people hate him, but Draymond Green has at least as much of a chance at third team as Hayward.
Anyway, I doubt Hayward quite sneaks into All-NBA. But I think he'll get a fair amount of votes, and it will be close. He's having a terrific year.