Always has been. A lot of prominent Twitter accounts in my primary language, especially the old ones, has telltales of having been on 2chan. net. There must be something to that format that installs a basic social media amplification skill in your brain that do not develop otherwise.

There are places more toxic than 4chan but skill levels don't compare, and 4chan and 2chan also share nothing culture wise, so it must be in the architecture.

That's understating it. They're practically the same at this point, 4chan just has fewer bots.