Nice callback to Moot banning an entire Australian region (Queensland or Victoria, if memory serves) because Aussies did an outsized share of shitposting, and of Aussies those particular ones were the worst.

That sounds old 2ch.net. Was that plan from Hiroyuki, by chance? IIRC they entrusted the key to kingdom to that guy, or am I mistaken...

That’s true, but to be fair my original comment also said posts would be reliably associable with other posts from the same IP. With CGNAT, that association will be slightly less reliable, but not meaningfully so. The segment of the population who posts on 4chan is so low that there is negligible chance of two 4chan users sharing an exit IP and time window. Even with non-overlapping time windows, the population will be low enough for stylometry (and other factors) to remove any remaining ambiguity.