I work as a programmer in games industry,and I feel like the problem is made worse by artists and level designers who add more stuff without worrying about performance. I can make a super efficient physics system or model loader,but that only means that someone somewhere is going to add more particle effects or lights or whatever, or maybe placing too many props in the scene so PS4/X1 can't handle it. In fact, the separation is huge nowadays - I know our engine inside out, but I personally wouldn't really know how to use the editor to remove things from the scene. Likewise, a level designer will know how to put props in the scene,but they will have no idea how underlying things are wired together or what is the performance cost of doing them.

It's a complicated problem, which might have been made worse by the fact that games are simply easier to make nowadays than ever before.