That's not exactly what happened. Yes, google did some shady stuff but in parallel Firefox was also slow for everything.
Only when FF Quantum launched the performance caught up, and the same launch gave power user a push to go elsewhere, coz all their plugins either stopped working or worked worse.
And it was too little too late too. IIRC the FF market share was already hovering around 10%. There were some people going back to it after Quantum release but that didn't last and were not at the level where companies like one I work for don't even test on FF because market share is so small clients don't require it
> Mozilla could make technical miracles and or bring some incredible feature from the left field, but that's a tall order for any company that size, so I'd expect most of their future effort to still end up with lower market share, whether or not they had good ideas.
Mozilla could, years ago, not focus on everything else but making a browser (Anyone remember Firefox OS ? nobody ? thought so). Firefox was on the top of the web and the management squandered it all.