Earlier quoted context omitted.
Even manually typing reddit.com/r/all (or r/All, which was a workaround for a while) in the address bar on iOS Safari redirects you to reddit.com/. Since I'm guessing you're not browsing reddit.com, what client are you using?
This is available for me on iOS https://old.reddit.com/r/all/
Anyways, the end result has been I don't use reddit at all on the phone, so kind of ended up being good for me anyways.