While I'd begrudgingly agree the two are not independent. I moved back to Firefox from Chrome exactly because Firefox became once again performance competitive thanks to Quantum. Most (all?) the big Firefox improvements were integrations of Rust code pioneered in servo. The only chance I see for Firefox is doubling down on that and replacing more and more components with those Rust rewrites. If not for that I don't see Firefox remaining competitive with Chrome for long.

I'd like to see Mozilla focus on Firefox, so that there it remains a viable alternative to Blink-based browsers for as long as possible. I think that may yet become really important as the effects of the incredible dominance of Google in the WWW become more apparent.

I'd also like to see the Rust ecosystem prosper, but I guess others can take up the slack, it is gaining considerable momentum and quite a few places are looking into it, or using it already. If that isn't possible, is there much hope for it anyway?