The idea that cost determines value is literally Marxism and it failed economically every time it was tried.

What matters is the end result, and proof of work is very bad even if cost is ignored - there were multiple 51% attacks on smaller PoW coins while even tiny DPoS coins work well, as far as the consensus itself is concerned.

PoW is insecure and extremely expensive. The writing is on the wall - after ethereum finally fully switches away from mining anti-PoW marketing is going to increase 10x. Supporting bitcoin will become synonymous with wanting to destroy the environment.