Sure, technology makes some things easier with time. But the needs for content to be optimized has not really gone away, and the issue was not necessarily overly complex 3D assets but that the very structure of what people wanted to build was difficult to optimize for. Many AAA games are set in indoor areas with no windows, because this limits how much you have to draw. In second life, almost everywhere the camera could see long distances either because you are outside or because you're inside in a room with windows. And that doesn't seem to have a really easy technological solution, although maybe Unreal's new nanite can do something about it by avoiding the need for custom LOD meshes.