I feel like some reporters are way too quick to default to the easy "explanations", oh look he was a Trump supporter, or he posted on incel sites or whatever. Usually it's far more complicated than that. For someone to kill people, to kill children, the person has to have serious mental issues. We'll have a "nocoiner who sold at $10k" rampage one day and we'll all be implicated once they dig up our Bitcointalk posts deriding that person.
Well, there's usually always some motive for mass killings and it's not just a random act of violence, but most incels will have some mental health issues: anxiety, depression etc which will contribute to their lack of success with the opposite success and it's a vicious cycle from there. From the video I saw I'd say it looks like a textbook case of an incel lashing out at the world.