They are also trying hard to become an advertising network:
Unlocking value while maintaining privacy of advertisers’ sensitive first-party (1P) data has long been a challenge for advertisers…
…especially appealing to advertisers who previously avoided activating sensitive data…
As far as i understand it, this protects advertisers from leaking the data they collected themselves from users to ad networks for free. Instead they can now monetize that data in a different way in the future, like selling. Wow Mozilla, much privacy innovation /s