The graph you linked shows Firefox topping out at around 30% of market share, a distant second behind IE.

https://en.m.wikipedia.org/wiki/Browser_wars#/media/File:Bro...

This later graph (from the same Wiki article) covers 2009-2022, and is much more telling: once Chrome launches, it overtakes Firefox in two years, and then IE in another year. By the time Firefox manages to overtake IE, it’s fighting for third and has only ~15% market share.

Today, Chrome has ~66% market share, and it’s somewhat clear that the remaining 34% of non-Chrome traffic is mostly iOS/Safari. Apple is absolutely being anti-competitive, but that anti-competitive position is the only thing blocking Google from taking control of client and forcing a browser monoculture.