After being abandoned by Mozilla, FirefoxOS was resurrected as KaiOS. For a while, it was the second most popular mobile operating system in India, mostly because Reliance decided to use it for some of their low-end Jio phones[1]. Where would FirefoxOS be today if Mozilla had stuck with it? If hundreds of millions of people had their first taste of the Internet via FirefoxOS and not Android?
I've been a Firefox user since 2004, but I don't think Mozilla understands how to conduct business. They're an ideological organization first and foremost. It's not a bad thing -- we need somebody to stand up to Big Tech -- but it means that they probably won't be taking a big share of any market except by complete accident.