I used FireFox for the same reasons, for years. Every time I started Chrome, it was a breath of fresh air. Everything was just slightly faster to react, to switch tabs, to scroll, to interact.
I kept reading posts about how the FireFox team was increasing performance, yet it never seemed to really impact it. Maybe because I often have several windows with a dozen tabs each (yes, one of those people.)
These days I have given up, and I haven't tried it for about two years now, maybe more. Is it any better? Does anyone know, for real, not a marketing blog post?
It still lives on the Dock, next to Safari and Chrome. I can't bear to remove the icon.
And Mozilla seems way off in the weeds with its product and corporate strategy. At this point, I'd pay for a non-Chromium, highly performant, privacy-first browser.