Yeah, the message should be changed and the contact email should be removed if it's not being monitored at all (or hire someone to start monitoring it). There are probably people who email it for many months expecting an answer and it's both futile and unfair to them to keep them hanging, and then it just causes more spam in Meta when they ask there. At the very least we could change the warning to something like You have been banned for breaking the rules. This is usually for copy and pasting content or spreading malware, but please see the full rules here to check what you may have been banned for. If you wish to appeal you can do so in Meta, but bans for copy and pasting are permanent. Or something like that. As I've suggested before having a button that issues the ban and gives the reason automatically as copy and pasting would also be solve this and probably shouldn't be too difficult to implement.
Firstly, most people who get perma-banned come back, unless they are so done with the forum. I don't see the problem with the current Ban message, it'd be easier if the banned users know why they are banned for. IIRC, some users were aware why they were banned for, as it was stated in the ban message.
But one thing, remove that darn email, we know nothing ever happens to those redundant crying letters.
Most people will just evade their bans. There's absolutely no checks from the admins whatsoever, even when we find 100 accounts and ban them all manually they could be evading on 200 more for all we know. You could even just create another one from the very same IP, pay the fee (if there is one) and you're good to go again. You'll only ever be punished for ban evading if you slip up and publicly link the accounts somehow and then you'll likely get red-tagged by the community, but any other accounts they may have that we don't know about are still free to roam around. And the only people who know what they're banned for are temp banned users as the reason is always given. 99% of permabanned users have no reason stated on their ban hence why they're confused and ask here.