"wholly owned subsidiary of the Mozilla Foundation" is the more important part here, because the Foundation is nonprofit and eventually has authority over the corporation, so the latter can't decide on its own to sell out.
The corporation needs to be able to make a profit not as an end in itself but to make strategic savings in case things get more rough with Google.
There's no other browser developer that's focused on user rights online other than Mozilla. These days it can't be just features and performance, though Firefox does not need any help in that respect either. Current version are simply brilliant.
> Net income: US$103.8 million (2016)
I wonder how rough things must be.
Have you checked Mozilla's expenses too? It has around 1200 employees, I think, and a few offices around the world, data center costs etc.. If you want to be able to independently keep that going for a few years, you need a big war chest.
Look at Dillo and Netsurf.
So if I go to Google docs, I can toggle spidermonkey (or whatever Firefox's JS compiler is called nowadays), but if I go to $randomwebsite, I'll get a secure and usable web.
I for one think that modern web standards are used by most web site authors not in users interests. Therefore implementing those standards in good faith not necessarily mean implementing an _user_ agent. Firefox is great, but web as it is mostly served is increasingly not. I just would like to see an user agent dedicated to users, not standards. Even if it would mean omitting JS and most of CSS. I would use it for information seeking and Firefox for necessary web apps.