I can’t defend what the guy did, but I think I understand how he got that way. Young men are often very frustrated and impatient when things don’t go their way. Our hypersexualized society, brought to us by the leftist media, has the “incels” believing that they are unfairly left out of a scene where hooking up is the norm. In an earlier era they would not have felt so out of place, because society was not telegraphing these values. They also would not have been able to form a huge community which reinforces their worst impulses. I have taken the time to read their message boards, and it is really sad and alarming. They are dug in, and they are mad. There will be more of these events in the future.
I have also read their message boards. They are scary people. Sad, but scary. They seem like powderkegs, and I see no mystery why all the women reject them.
One of the classic stereotypes of women today is the fat, ugly, crazy feminist — guys, you do NOT want to go out with her.
The Incels are the male version of that — ladies, you do NOT want to go out with them.