Many of these people overreact to good faith criticism and are narcissistic. There are some statistics that people become less self centered as they get older and incels definitely fall into that trap.

As for nazis etc, lots of that comes from like a lack of critical thinking about conspiracy theories. Its fine to think about conspiracy theories but the second you start embracing that like millions of people are conspiring against you to like stub your toe or something thats maybe the time to reign it in.