1. Under her leadership Mozilla has lost virtually all of its users. It has been reduced to less than 10% of what it had before, maybe worse - I haven't kept up.
2. At the beginning of Covid, a time when remote work was on the rise and tech valuations were through the roof, a time when the browser was more important than ever, she took her largest payout and fired hundreds of employees. She was compensated at over $5M dollars, enough money to pay a team of engineers for years.
3. Firefox has utterly failed to capture Enterprise market, where Chrome has managed to dominate. I doubt most people are even aware that a corp managed Firefox is an option, they have done such a poor job marketing it.
4. Every initiative Mozilla has come out with has completely failed to gain traction. Something like a VPN could have been a great fit for Mozilla but they did nothing with it. Mozilla has been incapable, organizationally, of capitalizing on technology - the thing they're kinda supposed to do exclusively.
She has failed in every conceivable way as a CEO. She has failed in terms of the mission, she has failed her employees, she has failed her users, she has failed to be an example as a leader.
Mozilla, as it exists today, is a convenient project for Chrome to point to and say "look, there's competition" - perhaps the only reason why Google continues to fund Mozilla.
Microsoft and Apple are at least competently run and have incentives to push to reduce Chrome's power.