As of January 2024, of the most popular 100 videos on Pornhub, 4.1 billion views were for step-incest videos and 3.3 billion views were for all other videos combined.
I know a lot of it is getting made, but I'm not sure it's actually popular. It's porn so a lot of people probably mute it and ignore the weird storylines
I would bet money that it's popular enough that it is worth adding those stupid, unrelated titles to videos. I bet pornhub models see increased views, and then title every video that way. You gotta play the game, and unfortunately the game is step sibs now.
I'm not doubting you can get more views, but I am doubting that many people specifically seek that out. It's kind of like an "add on feature" that you can ignore if it's not your thing. These are just people having sex, and the story is made up so it's ignorable