It's still a huge amount of work to support two ios builds for such a small audience. Also, the prototype they had no has jit because apple makes targeting ios a moving target (https://bugzilla.mozilla.org/show_bug.cgi?id=1904546), and it has never been polished enough for end users.

Not having JIT is a showstopper on the modern web where most sites take more javascript than all of windows 3.1 and word perfect combined.