We don't know whether this is another time that Mozilla execs have sold out users, or shipped something half-baked and vulnerable.

I'm not saying they're leaking the data (by agreement, or negligence), but Mozilla has mediocre credibility in recent years, and there's nothing on this page that improves that reputation.

Regarding Google, for a long time, their thinking seemed to be "We're Google, so of course anything we do is privacy-respecting", not as guidance, but to justify whatever they wanted to do. Also, every time Google gets caught with their hand in the private information cookie jar, it just mints a new industry standard practice.