I think the word they really want to use there is "indefinitely." It doesn't imply the same thing that "permanently" does.

Being pedantic indefinitely means "lasting for an unknown or unstated length of time", which kind of implies that the account will be unbanned at some point in the future. But I don't think there's an English word that conveys something will last for ever but could be stopped. Perhaps they should use "limited ban" for a temporary ban and "unlimited ban" for permanent or "permanent appealable ban".

I don’t get the ability to appeal. My Twitter account is permanently suspended and the appeals process is blocked for me. I have maybe tweeted once or twice years ago. I don’t get any explanation for why the appeals process doesn’t work for me or what’s wrong with my account.