Sometimes it feels like "Sure, Chrome sold my kids data to human traffickers. But I can't switch to Firefox because I really _need_ MIDI-2 over websocket support"
Sure, FF is not perfect but a lot of issues is due to sites being optimised for webkit and that will not change as long as Chrome has 80% marketshare. You need to sacrifice a little for freedom.
And herein lies the rub. 20% of people, at best, will sacrifice convenience for freedom.
Firefox and Chrome overtook IE because they were move convenient to use (Firefox had tabs and extensions, Chrome had a more reliable multi-process architecture and more CSS/JS/... features faster).
I use Ungoogled Chromium.
For starters, recent Firefox versions do proper process isolation per domain, similar to Chrome, which has long been claimed to be the primary security benefit of Chrome-based browsers.
In addition, the Firefox codebase is partially rewritten in Rust. This effort is incomplete and likely always will be, but it's still significant. Keep in mind that according to Google, 70% of security vulnerabilities in Chrome are related to memory unsafety!