Incels - whether they suffer quietly or play out their rage by shooting up schools - all have the same thing in common: A lack of understanding of how attraction works, and unwillingness to take responsibility to learn. It's just easier to blame women and decide there's nothing they can do about it.
I'm wary of PUA communities, because they would rather provide magic bullets than address the complex issues at the core of their problems. I speak with some authority on this.
I appreciated what Eben Pagan/Dr. Paul/Sean Stephenson and others provided, because I really felt they were getting to the heart of the matter, getting inner game handled.
But the truth is, that's not what people wanted. "Yeah, yeah, that's cool. Where are the pickup lines?" So they'd go right to Mystery, Owen, Nick, etc, who would literally set up a table right at a DYD seminar to siphon off people to give them what they really wanted.
Unfortunately, all the tricks, techniques, false time constraints, cold readings, canned conversations, etc didn't work worth a damn. Sure, a person could probably score after throwing enough game in an evening, but there was no long term success.
While some of the PUAs eventually did mature and find healthy relationships, most of them remain perpetual children, and are even unhappier now, because the thing they wanted didn't actually provide them the fulfillment they wanted.
Incels often seek out PUA communities, thinking this will solve their problem, and when the techniques they try inevitably fall flat, they become even more frustrated and even more entrenched in their belief that something is wrong with them, and now feel justified because they "tried".