“More serious, however, is the fact that Mozilla also activates the feature directly - users must therefore deactivate the PPA manually by opting out.”
Firefox 128 ships ad measurement switched on, and users have to find the setting to opt out. Mozilla’s excuse is that PPA is too hard to explain, so asking would not produce an informed choice. The tech comes from a company Mozilla bought, which now sits as the middleman between advertisers and users. The browser that sells itself as the alternative to Chrome now runs an aggregation server for advertisers.