I'd agree with this. The intellectual territory discovered in the 20th century is absolutely immense. It's like looking for water, and discovering an ocean - there is a LOT of filling in left to do with our current framework before the next frontier.
Physics is a good example- mankind is still struggling to apply quantum theory, 90+ years after its discovery. And it's not because the applications are limited - the applications will be fundamentally transformative. Complaining that we can't find other oceans is a little premature when we haven't even built a freaking ship to sail on the one we've found yet...
And physics is just one of many areas where the current state of theory and potential stand off on the horizon, mocking our feeble minds and capabilities. Maybe we as a species are just adapting to the realities of technological innovation, since it's much more common now. Which makes innovation the static starting point for whatever comes next to disrupt the pattern. Whatever that is, it's going to be similarly disorienting, in a different way.