If it wasn't valuable then the work wouldn't be done in the first place.
If it wasn't
profitable, it would
likely not be done in the first place.
Quite different.
Profitable doesn't imply valuable.
PoW is an unsustainable ever escalating arms race.
I told everyone upthread, the only way to make PoW work decentralized, is to make it entirely unprofitable. That is the last hint you are going to get.
So is the hint that PoS or something similar is the only solution? Satoshi chose PoW because of the greed incentive, he believed that the monetary attraction would bring enough people to the table that they would outpace any attacker.
If PoW is unprofitable, then the only miner will be someone mining for no profit, most likely an attacker.