TLDR: Mozilla makes money from Google paying it to be the default search engine on Firefox. If that practice is outlawed, Mozilla will not have any income stream even close to replacing that.
They definitely shouldn’t. Mozilla has talented engineers, but it’s been catastrophically mismanaged for almost 20 years at this point. Keep Firefox, but let Mozilla finally die.
I’m curious where you start it. I was thinking about it a couple of weeks ago and decided “more than a decade” was safe to say, but I was thinking towards fifteen years, not twenty.
Read through https://www.theverge.com/2020/8/11/21363424/mozilla-layoffs-...: six years ago, Mozilla laid off 250 people, about a quarter of their staff, in order to focus on… two specific services that they have since killed (Pocket, Hubs), one service completely unrelated to the browser (VPN, though they have recently decided to set more money on fire by integrating some VPN stuff into Firefox, where it never had any place and is frankly an affront), and new and unspecified “security and privacy” tools (probably things like Relay and Monitor) which are almost certainly completely unrelated to the browser.
They are focusing on things that are nothing to do with their core product, and have been acting so for a long time.
Mozilla is deeply unhealthy, and has been slowly collapsing for more than a decade at this point. I believe that the significant majority of its staff are doing things of no or negative value to Firefox.
I suspect that ten developers not beholden to Mozilla but with a mandate to make a good browser would be better custodians of Firefox. If you raised the budget to forty, I’m all but certain of it.
Safari doesn't run on Windows or Linux. WebKit does run outside of Apple's environment but no major browser uses it which means you are left Firefox, a Blink based browser or a WebKit browser that 5 people use.
Safari runs on many, many millions of various Apple devices though, and I think that more than qualifies it as a major/mainstream browser, and the same for Webkit as a mainstream engine... especially considering Safari's market share is ~5x higher than Firefox. You may disagree though, and that's ok.