Still, those of us who can make the mental leap should be allowed to buy the game if we feel like it.

If you can't extrapolate that to the act of experiencing the game by playing and not just watching it, then I fear you may have a point in that Steam is preventing ppl like yourself from buying it so you don't hurt yourselves.

Destin, when you decided to check out a playthrough of Horses on YouTube, you likely had read about the content in the game and you accepted to watch the video at your own risk. That's a choice you can make because you're an adult and YouTube as a platform respects you enough to allow you to choose.