8chan's primary crime is not being sufficiently popular.

The Christchurch killer livestreamed the event on Facebook, and the enormous well-funded content moderation apparatus within failed to shut it down until well after the innocents were dead.

But Grandma uses Facebook, so we can't go after them.

The Wal-Mart shooter had a Twitter account, and posted plenty of content questionable enough even for the FBI to take notice.

But cousin Jake uses Twitter, so we can't go after them.

It doesn't matter what 8chan was used for, because far more popular platforms were used for far worse content. The only thing that mattered here was popularity.

And 8chan didn't have it.