I agree about the first part, but have a slightly different hypothesis of why this is the case: The left holds the promise of solidarity and community, where everyone will be equal if only the classical leftist victimhoods (poverty, being female, being ethnic etc) are handled. Incels will recognize the falsehood of this promise by noting that there are still strict, if more subtle, social hierarchies governed by features such as looks and neurotypicality, and that he now is placed on the very bottom. As a reaction, he turns to the right, in part because it's in his own self-interest and in part because the right's recognition of social hierarchies seems more intellectually honest.