Is φοράει more common than φορεί?
In Cyprus we say φορεί. If someone says φοράει s/he sounds pretentious.
In UK english we say trousers, not pants. Would duolingo accept that as a correct answer? (In UK, pants are underwear!)
It is already accepted.
Why not "he is wearing"?
Why not φορεί?
As mentioned above, this is something the Cypriots would say.