Commercially, it's completely irrelevant. On big websites it doesn't even show up in the top 10 browsers and it's almost entirely absent on mobile. Site owners can readily ignore Firefox.
Firefox is no longer a developer default. I'm sure some of us in our bubble have strong personal preferences but the entire dev ecosystem is chrome-based. Very advanced devtools, Google having a team of "evangelists", course material is Chrome-based, test-automation, etc. So developers too can ignore Firefox.
Some argue that it's good to have an independent rendering engine. Here too Firefox plays no role at all. The only counter force to Google's web feature roadmap is Apple/Webkit, not Mozilla.
From a privacy preserving perspective, Firefox has no unique value. Install Brave, say no to the one-time crypto pop-up, and you have a very decent and fast browser that also consistently renders along with Chrome and Edge.
I use Firefox. If I ask myself why, it's muscle memory and because uBlock Origin still works.
I'd like to understand this point better. Does Firefox use the Chromium engine under the hood?
I've known my best friend for 50 years now, literally since kindergarten. One person. I probably wouldn't talk about my top 5% of private feelings with him, not sure why. I've been married 28 years now. She doesn't understand me at all, and doesn't want to see or hear any "weakness" from me. So what the f@#$ is an emotional support network? Science fiction, I'd say.
Maybe I missed the memo that we stopped hating monopolies? Every browser worth considering, except Firefox and Safari, is based on Chromium. Firefox and Safari make up about 20% global market share, meaning Chromium in about 80% [0]. A bug in Chromium is a bug in all of them. A backdoor in Chromium is a backdoor in all of them. A feature of Chromium, good or __bad__, is a feature in all of them. It baffles me that this isn't a bigger concern to more people.
I don't know what it might take for people to migrate away from Chrome en masse, but the alternative is there.