Chrissie Mayr did a stream where she interviewed Stuttering John. She made some off hand comment like "Oh so you dabble in standup?"
This apparently caused Stuttering John to sperg out or something. So weirdos all got together to form a community and identity around harassing him in real life as opposed to getting jobs, spouses, and moving out of their parents basements.
That's how the Dabbleverse got its name, but there's a bit more to the story than that.
It can be traced back to
WATP episode #109, where they reviewed The Stuttering John Podcast.
Stuttering John got wind of it, and started going after Karl from WATP pretty hard. Apart from an 8 month break from the Internet where StutJo may have gone into rehab and/or taken full time work as a substitute teacher at the end of 2022 and into mid 2023, StutJo has been at war with Karl and WATP since 2018.
Originally, WATP wasn't monetised, but once Karl turned WATP into his full-time job, grifters such as Shuli Egar and Cardiff Electric glommed onto the Dabbleverse, creating their own YouTube channels to milk Karl's paypigs.
After a while, Karl started introducing other lolcows into the WATP universe, including Steel Toe and Chad Zumock (though Chad seems to be going through a redemption arc of sorts). AFAIK NLO ended up in the Dabbleverse as a result of Fatty Patty being a longtime Steel Toe a-log.
StutJo is still going, but in the wider Dabbleverse he's now been overshadowed by Rackets and Steel Toe.
The original Dabblers from r/DabblersAnonymous were similar to the OnA Pests, only less savage and more playful. A couple of things have changed this dynamic to the toxic shitheap it is today: a cashed-up StutJo a-log/troll called Vince the Lawyer, and collision of the Balldoverse and the Dabbleverse. It's gone from being a bit of silly fun into full-blown Internet blood sports for middle aged men who should know better.
(and I'm ashamed to admit that I got sucked into the Dabbleverse as a result of following the StutJo/WATP beef since 2019... for the love of God, if you're not following the Dabbleverse, please avoid it like the plague)