Back when I first started using chrome it was the snappiest and had less memory usage than anything else on the block.
Then I started to think about what kind of tracking google was doing with it, so I tried out firefox... which was just as snappy and just as memory efficient.
I guess that performance gap didn't bother me at that point to switch to less privacy respecting browser and Firefox caught up well, so I never saw it as a problem.
Years ago I switched at a time when Chrom[e|ium] had a better developer tools console than Firefox (although only slightly better than Firebug). But, nowadays the console is equal if not better in Firefox to Chrome.
I don't trust Mozilla to not break my workflow or remove features I use or ignore debilitating bugs for upwards of a decade in some ham-handed attempt to "keep me safe".
That sounds pithy, and it is, but Mozilla burned every ounce of goodwill they ever had with me over the last 5 years or so.
So far, Brave hasn't done any of the things that caused me to abandon Mozilla. My browser is a tool, not a political statement. Mozilla has taken positive steps to make that tool less and less useful and waste more and more of my time.