It's a bit of a dog whistle, I just don't entirely understand for what yet. Basically you're better off not asking and going on with your life.
A charitable answer is, however, that a central source of income for Mozilla is Google paying them to remain their default search engine. Mozilla is hesitant to truly attack Google, as it would be biting the hand that feeds it.
More importantly though, Mozilla has a female chairwoman. A lot of tech savvy people would rather stick with Brave, whose CEO they can relate to.