Was it only hardcore porn? All I saw was 50% memes about nudity allowed and 50% basic nudity like boobs and pussy reveal by gonewild / only fans posters. Divnt even see softcore solo content let alone hardcore porn.
Except a small number that probably opted in for NSFW for getting spoilers or other non nude purposes, most already have nude content present in their feeds and use alt accounts. Going by the memes many did seem unaware of the decision to allow NSFW content, but given the site wide opt in it seems reasonable to allow.