According to that study, 23% approved of the statement "I approve hostile activism to drive change by threatening or committing violence". It's even higher if you only focus on 18-34 year olds.
Full report here: https://www.edelman.com/sites/g/files/aatuss191/files/2025-0...
A more likely explanation is that pro-violence propaganda began swamping social media in 2016, which is 9 years ago. 18 year olds have been exposed to it nonstop since they were 9 and 34 year olds since they were 25.
The people who are disposed to anger and violence move along the radicalization sales funnel relatively slowly. But already once you've shown interest, you start seeing increasingly angry content and only angry content. There is a lot of rhetoric specifically telling people they should be angry, should not try to help things, and should resort to violence, and actively get others to promote violence.
Being surrounded socially by that day in and day out is a challenge to anyone, and if you're predisposed to anger it can become intoxicating.
A lot of people want to say marketing doesn't work or that filter bubbles don't matter. But the bare facts are that we've had nearly a decade of multiple military intelligence agencies running nonstop campaigns promoting violent ideology in the US. And it would be naive to think that didn't make a difference.
The same sort of campaigns were run at a smaller scale during the Cold War and have been successful in provoking hot wars.
Those spaces used to be great places for people to ask questions, share interests, and find relief in a community that understood them. But over just a year or two, the whole atmosphere flipped. The focus turned from mutual support to a shared antagonism toward neurotypical people, who were often dehumanized.
It was heartbreaking to watch. Long-time members, people who were just grateful to finally have a place to belong, were suddenly told they weren't welcome anymore if they weren't angry enough. That anger became a tool to police the community, and many of the original, supportive spaces were lost.