Kind 30064 is NIP-95 files. Given that I run an explicitly sex and porn-friendly relay I don’t want to run the risk of actually hosting child porn.

Good call. But NIP 95 is not your main problem. I assume you know that people can do this with any event kind. If they just want to turn your server into a storage of illegal content, they have all the nips available to do so. I would target the intention, not the tool.