The ‘why’ came as a shock to the studio. “While we strive to ship most titles submitted to us,” Steam’s automated response read, “we found that this title features themes, imagery, or descriptions that we won’t distribute. Regardless of a developer’s intentions with their product, we will not distribute content that appears, in our judgment, to depict sexual conduct involving a minor. While every product submitted is unique, if your product features this representation—even in a subtle way that could be defined as a ‘grey area’—it will be rejected by Steam.”

Nor, says Pietro, would Valve elaborate on its rejection, despite repeated requests for clear answers in the months that followed. “Did they think that the protagonist looked too young?,” he ponders, “Did they think that the horses look too young? Did they think that some of the actors in the live-action sequence looked young?” In a lengthy FAQ detailing the ban, now available on its website, Santa Ragione notes all characters in Horses are "clearly older than 20 years old, as communicated by their appearance and through dialogue and documents that you will encounter in the game."

Yeah gonna have to disagree with you there chief. This is some dumbass stupid censorship. You can play games on steam where you bend people over a bar and fuck them.

Those people are also older than 20 years old. So what makes this different?

This is surely some of the fallout of MasterCard and Visa swinging their dicks around and being pouty that humans like sex and some people want to consume legal content that contains it. (Edit: actually this one point doesn’t stand as he said later that this was before Valve bowed down to the financial processing overlords and did mass adult bans)