I use Firefox exclusively on Desktop and Brave exclusively on mobile. Firefox on Mobile still has performance issues for me.

I also have a S20 FE and can attest to the bloatware they install with each software update.

Samsung is pretty much notorious for this, especially in developing countries where they bundle in every third-party service, PayLater app, shitty mobile game, etc alongside a new device. The only reason they are seen as preferable is that other companies are doing worse (see: Xiaomi).