He's played 5 games.
Do you really think professional D coordinators need 5 whole games of tape to find a guys' weaknesses?
That dude instantly made the 49ers an infinitely more dangerous team the second he stepped on the field and he's doing it in a way that is sustainable.
I'm sure his numbers will drop in the postseason simply by virtue of them playing better competition every week, but you can bet he's not going to go full turtle the way Garoppolo inevitably would have. They'll be in every game they play and Purdy's brains and balls will be a big reason why.