Firefox is quite usable on an iyonix. On a risc pc it is too slow for general use, but having it available as an option would be useful for those odd occasions.
I can quite see that not having it available on slow machines while it is being developed is very desirable.
My Risc PC is only twice as old as my Iyonix and not much older than the oldest Iyonixes, if I had bought it new, I doubt I would have purchased an Iyonix. I suspect there are quite a few people with RPCs that are relatively new who can't justify an Iyonix.
(And I do know that some of the I/O is on a par with a 286 PC)