Wasn't Privacy Pass supposed to fix this? Let the browser generate and store some PoW or something that it hands off to the site, so each site doesn't have to do the same thing.
https://github.com/cloudflare/pp-browser-extension seems kind of dead (a dependabot zombie).
eta: I completely missed this two days ago: https://www.cloudflare.com/press/press-releases/2026/cloudfl...