I admire the human belief that the improvement of technology and our living standards will be infinite. It will be a bitter moment if we finally realize the plateau we've been stuck on is not temporary and all future gains will be marginal.
This realisation is by definition wrong, or coincidence. You can’t know the future, so you’ll never know whether something will eventually come around and change everything.
I think this is a great point. It's not a robust counter-point, but Gödel's incompleteness theorems come to mind. We do know there are limitations to formal systems, we think there may be limitations to computational complexity. Maybe we haven't developed the tool set to make similar claims about biology (or maybe such tools cannot exist) or technology in the abstract. But these may also come in the future.
Fair enough. If we reach a point where we’ve discovered all fundamental truths of the universe and no more knowledge is helping towards solutions we need, then yes, that may imply awareness of the plateau; I’ll give you that. It also seems fantastically far away, so much so that it seems an exercise in futility to speculate about it.