Or like anything else it will be too good to be true at the very beginning but then once people hear about it and it gets popular supply overtakes demand and the mac minis go back to being idle most of the day.

When YouTubers start making videos about it you know it's too late.

The question is what is the hassle of running it plus wear and tear. Max price will tend to that. It is not like crypto where there is capital investment in a rig that can do nothing else. People are using their existing laptop. So I reckon 20-50 a year max per laptop.