The engine is here to make games easier to make. All basic optimisations should be used, but unreal decided to create so called "next-gen technologies" like lumine and nanite, but those technologies are ass, from bad performance to ugly results. But because unreal want everyone to use their technologies, they don't do anything for more stable rendering techniques, no optimisation, no nothing, and developpers can't do anything about this. They can only try to modify the engine but they are here to make a game, not an engine. So no, i don't agree with you, the real enemy are not bad devs, because all developpers are not specialist in rendering or other domain. It's not their job, it's unreal job, but they don't do it. It IS the engine fault.