I mean, the great players get out of the pocket and make great throws or run for yards. Mahomes avoided Bosa several times and in the end he made the big play. Of course there were other factors but when Mahomes continues to do it over and over, you have to concede that he has that factor that a guy like Purdy just doesn't have.
Purdy is a good game manager. Probably in the range of Cousins, but he isn't likely to take over any games against good to great defenses.
But, yeah, this game was mostly about defense which is why it takes a guy like Mahomes to make the play when it counts. And, it doesn't hurt that Andy Reid is a great play designer and caller.