There's probably also the cultural aspect around it. Most people still feel pretty ackward with all things related to sex. Just talking about it is taboo. Most people feel more comfortable just not bringing the topic. Even with the amount of porn being consumed, you'd be hard pressed to have anyone talk about their porn consumption to anyone else, including their sexual partner.
It's not been very long since sex can be had safely either. For most of history, sex came with lots of risks, like pregnancy and diseases. In my opinion, it'll take a few more generations for safe sex practices, safer sex work environment like digital sex work, and all that to catch up and start changing people's attitudes around it. Not sure that SV investors can do anything about that.