Perhaps you didn’t see the (deleted) comment I was responding to, but they were speaking from the position of a web developer, not from the perspective of a normal user:
I’m a software engineer, and when I build web apps, Firefox now stands in the way of me being able to use new standard features (without polyfills). Meaning, if I want to support the 2-5% of users that may use Firefox, I have to explicitly go out of my way to either make my site less efficient for everyone, or build a special version just for Frefox because it’s so behind, like we used to with IE, making Firefox the new IE (except nobody is really using it). And of course, you can only polyfill so much. Some things are utterly impossible, such as the various PWA features that Mozilla refuses to support, or many new CSS features coming out.
Perhaps you didn’t see the (deleted) comment I was responding to, but they were speaking from the position of a web developer, not from the perspective of a normal user: