We had it in the era of America's greatest relative growth (by some measures at least) in the 1950's-60's,they were called beatnik's. The conversation around them at the time tightly mirrors that about tangping today.
I've been saying for a while now that China is undergoing a Mccarthy era politically, and that their "summer of love" is less than two decades away, and they'll be radically tranformed by it.
Thanks for the metaphor with the Stirling engine, hasn't heard of that before. Interestingly I've always considered capitalism to only work in a system without scarcity of resources (land, minerals, ect.) as it's often the most efficient way to extract those resources and convert them into more useful products (by humans subjective standards). It's when raw resources are limited that the paradigm for endless extraction breaks down, as there's nothing more to extract, and quality of life starts diminishing as we extract beyond replacement level of natural resources.
But I think your point is about scare processed resources being the motivator for capitalism, and that once the gradient diminishes and the top is warmed enough, and the heat differential with the bottom is less, certain members will opt out of further extraction. This is why inadvertently a lot of conservstive lawmakers advocate reducing entitlements, to artificially "cool" the top plate, to keep the engine turning, even if they don't know for what purpose.
Still, communism even in it's converted versions has not worked (I'm sure you don't seriously consider China's economic system one that is concerned with equal distribution of wealth among the working class right?) and has brought many horrors to those living in states that claim to be using its doctrine, and those failures must be accepted and addressed before better alternative approaches can be considered.