You're assuming that the alternatives are actually physically able to meet demand. If that's the case, then great -- what you describe would occur. If not then the only alternative is demand destruction. We can handle some amount of demand destruction in the form of cutting wasteful consumption, but too much would very rapidly disintegrate into... well... actual destruction.

I think a lot of people oversell nuclear power. It's true that there's a lot of irrational FUD about it, but the real reason it hasn't taken over isn't that. Greenpeace protests coal but that doesn't stop anyone from using it. Radical greens are not really that powerful. The reason nuclear hasn't taken over is that it's an expensive, finicky, difficult to manage and scale technology -- at least in its present form -- and has several "unacceptable" failure modes in worst case scenarios. I also suspect that the fossil fuel lobby has worked behind the scenes to shut down research into better ways of doing nuclear, since better forms of nuclear power that did not have these massive downsides would be genuinely disruptive. Multi-trillion-dollar industries are far more powerful than hippies.