Name one other browser that is not based on Chromium. If it is based on Chromium, it has to deal with what Google throws at them.
I say this as an enthusiastic Brave user. Brave is great at what it does currently, but the more terrible stuff Google builds into Chromium, the more patches they’ll have to maintain. This can make it harder to maintain their fork.
Worse than that, most Chromium-derivative users aren’t Brave users. Many web apps already don’t work as well with Firefox’ JavaScript Engine (Gecko) as they do with Chromium. This gives Google immense power.