I agree with the author though. IMO the existence of so many "incels" is some expression of a real societal problem. Many young men are suffering, and we don't acknowledge their suffering as genuine. We just tell them that they suck, call them names and walk away. This can cause them to become more radicalized.
I was raised by a mentally ill single mom, on welfare. In many ways, my emotional maturity really lagged behind that of other guys. I didn't know how to make friends, let alone how to approach women or form a healthy relationship. I did eventually manage, but it took me years of learning during my 20s. When I was a young man, I struggled with some pretty bitter feelings myself, and I feel like society didn't make it easy to overcome them. Even today, the not so ambiguous message that society sends to young men is: if you can't get women, it's entirely your fault, because you are not enough. It just adds insult to injury, particularly when you're really missing closeness and understanding, when you feel alone and wounded.
IMO, the modern discourse around gender only really goes one way. We hear about women's issues everyday, but even in 2021, it's no more okay for men to talk about the challenges they face than it was in the 1950s. Men are told to just suck it up, and that's a huge part of the problem. If feminism is really about gender equality, then it needs to allow some room for men to talk about their issues and concerns as well, without fear of judgment. I would also like to see words other than "toxic" being used to describe masculinity.