Firefox is better, but it’s no surprise it isn’t mainstream.

1- A lot of businesses default to Chrome or Edge on their machines. Even if individual employees want to change it’s not like they have the ability to do it. Thats a huge amount of locked in Chromium traffic.

2- The vast majority of personal users are not tech conscious. Consider that only about 1/4 of people use ad-blockers. If the majority of people don’t bother installing ad-blockers why would people think they would install a new browser that has fewer immediately obvious benefits?

Online tech discussions have a tendency to vastly over estimate the tech savvy, and the expectations of most users. Just because you or I configure our computer experience, and think it’s a simple exercise doesn’t reflect most people who leave everything on default settings and simply live with whatever is thrown at them. This is just like the discussion on Netflix cracking down on account sharing, techies predicted a massive wave of piracy without understanding that most people don’t know how to, and are unwilling to learn how to pirate.