alt Hacker NewsFF is plenty competitive on the technical and feature front. It's market share is not a reflection of technical merit.
What's more, next to Linux itself it is maybe the only case I can see where a major piece of user facing software is kept competitive with the Apple/Google/MS tools.
LibreOffice or Nextcloud are technically far further behind Office and Google's online offerings.
Which therefore begs the question: Who else is in a position to do this?
At first glance, Moz with Firefox + a suite of self-hosted team and productivity stuff that works well in Firefox would make a ton of sense...
It isn't competitive. They are paid by Google.
Worse, it's ridden with spyware, and is merely a honeypot for security-aware people that are not sufficiently paranoid to check any of the claims. Like, those VPNs from YT ads that use your IP to give AI companies residential proxies, the same kind of scam.
Spin up Wireshark and take a look at activity of Firefox. Try to shut the browser up. It won't work.
Even if they weren't a Google's proxy company, they would lose to standards commitees being infested by Google, and would have to play the "best luck catching up" game by constantly supporting new versions of JS, APIs and CSS features that nobody needs (except Google's YouTube will use them to stop you from using an adblocker).
FF is governed by ex-Oracle managers at the moment, singing the Google's song. Don't anthropomorphize your lawnmower.