Not only does disruptive innovation not happen where we expect it to, it usually refuses to happen where we will it to. Not only solar (and fusion) power, but things like making the kind of artificial intelligence we wanted. It seems like they were just not solvable with any amount of cleverness. Maybe we picked the wrong build tree, but maybe we were just hand-waving when we extrapolated to flying cars.
I think part of the problem is not seeing sustaining innovation, like nearly all of the space program, as the mostly-linear kind of innovation it is. I mean, it sure seemed like we were creating new dimensions of technology when we increased the "number of men on the frickin' moon" statistic above zero. But how much of the innovation required to get there was really Freeman Dyson level stuff? To me, the 25-year line from V-2 to Apollo (with stops at satellites and ICBMs) seems pretty straightforward given the resources involved. Am I just too jaded by retrospective?
It seems the fault lies more in our expectations than in our imaginativeness.