People get so worried about "traditional" PF's.
If this was late 80's into the early 2000's, yeah it would be an issue. You had to have two guys who could guard (as best as possible) against the Shaqs,Mournings/Yoa's for the league. You needs a PF that could switch off if need to guard these guys.
Not too many to the back Centers and PF's any more. Most PF's work 3pt line in.
Stevens runs one small, three wings and one big usually. So what ends up happening is who ever the wings are matches up who they can guard best.
Plus they should have the mentally of not worrying who they have to guard, but make the other team have to worry. Hopefully Hayward or Tatum develop a post game, and if their guards match up to one of them, take them to the post, make the other team adjust if possible.