I had a sub on reddit, r/AmazonRedshift, for two years, which about two months ago was deleted, without warning, reason, notification or any mechanism for appeal, I think by an automated system (the owning account was shadow-banned, which is to say, you're not notified of it, and when you browse your own content it all looks normal, but no one else can see anything you ever posted).

I had a second Reddit account I used for non-Redshift stuff, which I've not used now for a couple of months. The two accounts to my knowledge are wholly unconnected.

I logged in just now to have a look. The account has been permanently banned, as of two weeks ago.

The reason, and this is exactly what is written in the automated message, is;

"Your account has been permanently suspended for ."