The 'Brand Safety' and 'Suitability' industries have financially crushed the news business by keeping ads away from articles that its 'sentiment analysis' algorithms think will make people sad or upset.
They do already exist, it's just for a much smaller market so it flies under the radar. Advertisers pull out of YouTube due to strong language and others happily slap their apps on porn sites.
I mean a lot of ads are scammy but also there are plenty that just point to adjacent adult content services like other sites or toy selling sites etc. Regardless it's a profit for whoever runs the ads.