I remember burstcoin and they were a thing around 2017-2018 but it didn't gained traction. And I think that's because of the trend that keeps on changing on the market, they're left behind. Maybe, if some big corporation will start to adopt and implement mining through PoC, it might get an attention these days.

You've said it already and one thing about it is that it's less profitable than PoW and PoS.