That post is nearly 2 years old. Have you checked for evidence that any of those accounts changed hands?
Change of account ownership is a risk that is always there with linked addresses. Even if the accounts have been linked by addresses posted recently, it is not conclusive evidence.
Case in hand - User Multipulty perma-banned for copy-pasting.
https://bitcointalk.org/index.php?topic=1163169.msg17065171#msg17065171He has 5-6 alts which are linked by addresses posted a couple of weeks back.
But this doesn't result in an auto-permaban for the others.