It should be pretty self evident that no one is expected to go back and scrub their posting history of any mention of HP....
Moving forward, a thread on how great LEGO Harry Potter on the Vita was would certainly be locked.

Straight up gaslighting people how era mods operate here - pretending like it's not even common for mods to drop a ban reason mid thread then retroactively go on a banning spree

It should be self evident forbidden subjects are enumerated somewhere so as to avoid inadvertent rule breaking
It should be self evident that rules are listed and rule breaking cites specific rules when being moderated
It should be self evident that moderators who want to post like regular posters should have a clear division between when they are just posting opinions versus acting in an official capacity, and not pull petty power tripping asshole moves like banning people for a disagreement, or responding in kind if that moderator is being overtly rude or hostile
It should be self evident that even taking situational wiggle room into account, certain posters shouldn't have a preferred status where they are not held to the same account as regular posters
It should be self evident that there are numerous forum tools available to moderate discussion without jumping to the last resort of bans, such as word filtering unwanted words, phrases, or links, issuing warnings to posters who are getting overly heated or expressing opinions too controversial for the majority, or thread banning people who are derailing but who don't make a habit of it
The fact is Master Of The Rejecting Reality And Substituting Their Own Stone is literally in a thread whose two recurring themes are 1) why is so much of the ahit mods decide literally the opposite of 'selr evident' and 2) why do the mods find it so fucking impossible to concede their mistakes