Another way of thinking about this is that large companies have basically decided that executing optimally is more important than necessarily creating huge leaps themselves. They can just focus on making money, create a sizable amount of cash, and acquire new technology.
I'm sure there's a cultural effect here as well. Seems like there are fewer large companies that are willing to just let technologists "muck around for a bit" swinging for the fences without some kind of goal.
But, I just wonder, if VC-funded startups are where new tech grows, we end up just focusing on incremental improvements, instead of potential large leaps.