The first time someone used the phrase "horny jail" unironically and wasn't slapped into the following week
Maybe I'm incorrect but I always thought this came about because people went so ridiculously in the other direction where their dopamine-receptors were completely captured by pornhub, that it was a polite way to bop them on the nose for being a gross gooner in completely non-sexual contexts.
Like anything amusing on the Internet though, it simultaneously started to mean everything and nothing at all, I guess. Lol