The laws of physics still apply. We already have to do all kinds of crazy tricks to make transistors as small as they are and not leak electrons all over the place due to quantum tunneling. The best thing we figured out how to do is just pile on more CPU/GPU cores.

It's also arrogant to assume we will continue on this exponential industrial-revolution growth of the last 300 years and not plateau as a species again for the next thousand. We could be looking at an eon of just burnin' away our oil while we try to cling more and more to whatever other energy impinges on this pitiful little planet, trapped in our local space unable to use our pathetic spacecraft to push us any further.