"No mass murderers have been users of forums explicitly designated for inceldom."
https://incels.wiki/w/Main_Page
When you have to make a statement like that about your community, it pretty much indicates you have a problem. Imagine if anarchists were to say, "No mass murderers have been users of forums explicitly designated for anarchism" or Alt-Righters were to say "No mass murderers have been users of forums explicitly designated for the Alt-Right." It would tend to indicate, there probably have been mass murderers who were users of forums that weren't explicitly designated for those movements, but had something to do with those movements (maybe implicitly).
Incel is not a movement or a community, but a gender-neutral life circumstance.
Then why don't they allow femcels or trannies at Incels.co? They're just trying to say that so they don't seem sexist or misogynistic. Anyway, knajjd, Master, and mental_out and others have talked about the existence of "the incel community" although Incel Wiki's article on the incel community mostly just serves to deny its existence.
https://incels.wiki/w/index.php?title=Incel_community
Basically this just boils down to an attitude of, "Please don't hurt us! We're not an organized group and therefore we don't pose any threat to the establishment." At the same time, they do stuff like have a Twitter account for outreach about current events, which is characteristic of a community or movement that's trying to be relevant. So it's like they're trying to have it both ways.
Incels are a demographic that is highly diverse politically, racially, religiously and socioeconomically.
I would bet you that about 90% of incels are brokecels. Even a lot of 18-yo youngcels would probably ascend if they inherited a million dollars suddenly and had access to that money. Women are lazy whores and want an easy, cushy life with financial security provided by a man.