While I can definitely understand seeing their average behavior as a compromise between the subject of this thread and something healthy, everything that they do harms themselves and others. Even if HIV weren't at such epidemic levels that they need screening rooms at MFF, the only reason to actually go out and have the "sex" is confusion and insecurity. It's already a mental shortcut, so why wouldn't people further down the hole just carry the abstractions that sustain it a bit farther? Sex positivity absolutely caused this.
Take a serious look at the people who have "sex" at conventions. Look at how they post about it, their mannerisms, and the nervous narcissistic sexual energy around them. These aren't people who just saw someone really attractive and couldn't control themselves; they're there to live out the roles that they reinforce with their pornography. Before they hit puberty, these people expressed their energy through the sorts of creative works that the rest of the autistic part of the internet are known for: fanfiction, webcomics, and OCs. Most of what they create now is just a sexualized version of that, with the caveat that a part of the broader LGBT "community" is attached that only sticks around for porn/"sex" and doesn't share that history or psychology. If the kinkshaming isn't as high as physically possible, you're inevitably going to see this downward momentum.
