Not sure what you mean. There is an incredible amount of porn on twitter. Just do a search for almost any non porn term and you'll find it.

Probably the only place you wont find porn is gab.

For me the issue on nostr isn't the porn itself but that we don't have universal nsfw filters etc so that porn is marked in case you're somewhere that viewing it could get you in trouble or so that you can remove it from your TL easily. I don't want people wanting to remove the bridge because of it (especially since there is some porn directly on nostr)