>>713123502 (OP)It's really simple.
The game has a deadline, anon developer's boss has a choice on where to spend the money:
implement new feature X which the focus groups say will definitely sell copies.
Or go hunt down why there's massive fps problems in Y dungeon.
The PM picks new features every time because people will still buy the game if the dungeon runs like shit, but absolutely will not buy it feature X is missing.
All ue5 does is make it even easier for the PM to choose new features over optimisation because it lowers the bar on how difficult it is to implement them.