Uh, what? Content Blockers on iOS aren't scummy, they can't track you because all they do is provide filter lists to the OS, which then runs them against your browser traffic. They work just fine in Firefox. Firefox Focus provides its tracking protection list as a Safari Content Blocker, which is nice. Other than that, I use AdGuard because it's free and lets you choose which filter lists to use.

You have to enable content blockers in Settings → Safari → Content Blockers. Just downloading the app without following the instructions is not enough.