> The assumption that PoW is wasteful is one with an ideological basis that comes from a lack of understanding of the purpose PoW serves

I agree with this, but I think the real problem with PoW is the mining pools centralizing. People seem to think the recent swift soft fork is something to be celebrated, but I think it's kind of scary how swift it was. It just means that the mining pools are so centralized that the transition was so easy.

Then again, this is something even PoS will probably suffer from.