I don't think I agree with that. To me MKG being 19 is WAAAYYYY more impressive (notice the caps!) than if he'd been a 4 year college player. Regardless of whether you think that playing college is any sort of help in production you can't deny that playing more years in a structured setting has to help an individual's development. We have that as proof right now vs. last year if anyone has any doubts.
I said, age doesn't matter. IF MKG had stayed another year, and thus (stay with me here) entered the league as a 20 year old and still put up the same stats, it would be equally as impressive.
If MKG entered the league as a 22 year old Senior, it would be (you guessed it), just as impressive. The NBA is a completely different beast than any level of college. Being able to immediately make an impact is noteworthy no matter how old you are.