For an analogy: Tim Cook is a great manager for Apple, but I don't believe he would be a great founder of something similarly big on the contemporary smartphone market.
Mitchell Baker is certainly passionate about things, they're just not the things which push Mozilla forward in competing with the Google-Microsoft-Apple trifecta. She is compassionate about her own remuneration, having increased it manifold [1] over what Eich took while overseeing a decline in market share by 85%. She is compassionate about "social justice", using both Mozilla-the-organisation as well as funds from the Mozilla foundation to push "racial justice" [2], "diversity and inclusion" [3], "environmental and climate justice" [4], "alphabet justice" [5] and more - just do a search for "Mozilla foundation social justice" for more examples.
Baker is not as interested in developing a browser, that is comparatively boring and does not give you any virtue brownie points so it was not that hard a decision to fire 250 people [6] to become a 'more nimble organisation' which coincidentally left more money for those other purposes she wants to pursue. Who needs developers after all when you have an internet full of volunteers?
In short, Baker needs to be fired if Mozilla is to have a chance at rising again like the Fenix or Firebird it once tried to name their browser after but which names got shot down due to trademark conflicts.
[1] https://en.wikipedia.org/wiki/Mitchell_Baker#Negative_salary...
[2] https://blog.mozilla.org/en/mozilla/leadership/mozilla-racia...
[3] https://www.mozilla.org/en-US/diversity/2021/what-we-build/
[4] https://foundation.mozilla.org/en/blog/intersections-of-digi...
[5] https://blog.mozilla.org/en/mozilla/mozilla-supports-lgbt-eq...
[6] https://www.techspot.com/news/86331-mozilla-laying-off-aroun...
It is possible that if Brendan Eich stayed, some other people (developers passionate for gay rights etc) would leave. But the disastrous plunge in market share that was brought about by the current vanilla leadership is, IMHO, a magnitude worse than what that controversy would be able to bring.