The mainstream didn't get mainstream by striving to go with mainstream. They got there by serving a niche well and then expanding the niche. Trying to go mainstream without having a niche moat will make you lag behind the establishment endlessly.

I'm not an Apple fan (rather an Apple hater if you would), but they are a perfect example of this. First, have a top quality niche product, then go into the big waters with the vision you got from the niche - and then people will actually be willing to give up bells and whistles the product that is good enough.

Mozilla have a well-established niche with a vision, but they can't monetize without giving up the vision they have (and apparently consider opening for small direct donations or maybe even direct bug/feature crowdsourcing not worth it). So they keep jumping on every sidetrack. And keep losing even the niche they have.