They also artificially shut down the apparently fully functional extension ecosystem on Android for no given reason, despite repeatedly stating that they would not do so. There still is one purposefully complicated workaround to use all store extensions, so we know it's about power, not compatibility. The crucial ability to use non-store extensions was entirely axed during that transition, also no reason given. This is how they were able to ice out anti paywall extensions recently.

Mozilla management has a history of consistently steering Firefox towards being less and less of a user agent.

This is why I think that if you trust Mozilla as a steward of the Firefox browser, you have not spent much time following their behavior.

I’m not trying to “move you to outrage”. I’m not the person you asked nor a Firefox user, I have no stake on what you think about Mozilla. But you did ask what Mozilla has pulled that would get someone to distrust them.

Perhaps you trust Mozilla to the end of the world, but for some people all it takes is one particularly bad incident to completely lose faith. You have your own threshold, other people have theirs.