Google didn't use anticompetitive practices to squash it. They just made a better browser. When Chrome came out it was significantly better than Firefox. That's why people switched.
To be honest it's still better (at least if you ignore the manifest V3 nonsense).
I think it's pretty debatable that Chrome is currently better, but you're definitely correct. When Chrome first debuted (and for years afterwards) it was clearly superior to Firefox.
To be honest it's still better (at least if you ignore the manifest V3 nonsense).