If people can somehow keep cryptocurrency values high, they can take USD margin loans out of their Bitcoin holdings, which increases the amount of total dollars laying around. That’s what happened in 2021 that bumped crypto asset prices due to extremely low USD interest rate and quantitative easing. In terms of USD it is really not zero-sum, though you may take it in other ways.

Worse than that, it's actively undermining a system of laws and fair play that do create stability and value. It's strip-mining a rainforest for kicks. I came to Bitcoin naiively as a libertarian curiosity and after examining it fairly closely I'm convinced Satoshi was a black market kingpin and Bitcoin was conceived as a money laundering vehicle.