PoW(hatever) is a cancer as long as the "Whatever" doesn't have any value behind it, it doesn't bring value to society because it's guaranteed to take resources without leaving anything useful behind. It incentivizes people to abuse anything at hand to obtain proof of that otherwise worthless "Whatever". Whether it's "work" or "space" or "time" then someone will always look to abuse others to obtain more proof without it creating any value.
Unlike money (generically) PoWhatever cryptocurrencies aren't backed by anything anyone can define as valuable. Proof of Housing_built, Proof of Goods_transported, Proof of Music_created, Proof of Space_flights all create real value. Proof of Work where the work is without doubt useless in itself and an absolute net loss for society can't result in anything practically valuable. At best it results in a very wasteful Ponzi scheme.
Imagine something as innocent as "proof of clapping hands", you may get some reward for holding a record but it's otherwise completely useless. That at least only affects you and your hands, even if a waste of time that doesn't seem to bring anything of value - joy or other practical benefits. What if someone could abuse you and force you to clap at the cost of lost productivity at work, health issues, etc. and the result of that work is... nothing?