I think this is different. I hadn't heard of Kiwifarms before, but I looked it up in 10sec. Looks like they were a forum for people to actively harass others - which has always been and should remain illegal.
"Specific Person is a real jerk! And they probably eat live frogs for fun too! What a loser!" - As long as Specific Person can effectively ignore this - meaning it's not forced into their feed, overwhelming their inbox, etc - then that's probably fine, even if untrue.
"Specific Person might live near XYZ. Definitely DON'T put any turds in their mailbox ;-) " - Pretty clearly an invitation to real-world harassment, which is not okay and should not be abetted by any platform.
"Specific Person is a real jerk! And they probably eat live frogs for fun too! What a loser!" - As long as Specific Person can effectively ignore this - meaning it's not forced into their feed, overwhelming their inbox, etc - then that's probably fine, even if untrue.
"Specific Person might live near XYZ. Definitely DON'T put any turds in their mailbox ;-) " - Pretty clearly an invitation to real-world harassment, which is not okay and should not be abetted by any platform.