Intel recently encountered production difficulties that cramped its ability to retain the lead in the shorthand of Moore's law. The company is bring 14 nanometres into range on its chips with 10nm achieved in the laboratory. So currently, there is no brick wall ahead. The latest hiccup was a rise in defects in the new chip process: down to manufacturing errors and not to fundamental limits.
And if there is an example of how economic incentives can redouble, by orders of magnitude, the computing capabilities of hardware, then the challenges of Bitcoin mining give a keen example: you can no longer create new money on your PC. The technological race transformed "don't do this at home" to "can't do this at home".