If you look at past socialist revolutionaries, you'll find that most of them actually came from the well-to-do - it's the fear of "falling off" of the nice things they're used to that often triggers an extreme response. This is why civilized countries need to take the idea of inequality seriously - I've seen a lot of people in tech justify the widening gap between the haves and have-nots by claiming they're "helping" people in the very poorest levels (there is some truth to this), but it's of no comfort to the people living right next door.
This pattern started around the "Web2" era, where the internet started to become more centralized - more hierarchical - more unequal. The early days of the internet was chaotic - but largely decentralized since nobody really knew what was going on anyway. After it became more "structured" (e.g. Facebook, Google, Twitter, etc.) that's when people started feeling like they were being "left behind".
This has been going on for a while already - I remember a professor reminding us that shootings in schools happened all the time, especially in poorer neighborhoods, but Columbine was a "big deal" because it started happening in more affluent areas - including universities and colleges as a whole.
It takes a level of education to understand the idea of "systemic injustice", and it shouldn't really be a surprise that high profile murders like these were conducted by people who have some awareness of what's going on. High education + poor economic systems tend to lead to political strife, and the situation we're in now is very much similar to what has happened in the past - the rise in popularity of socialism, political violence, increasing socioeconomic inequality, and high unemployment - all of the signs are there.
The last time the US experienced this kind of thing was during the Great Depression, and arguably the 1970s, where a similar cultural revolution took place. All the signs? Pretty much all there. But what's the one thing that's missing? A crash in the markets that helped to lower prices of everything, providing at least some relief for those struggling at the middle and bottom.
I think after this week it made it clear that my predictions are probably right - and things are going to happen exactly as I thought it would. It's not so much that I think that it's "going to happen", but more that it "needs to happen" at this point. There really is no other way.
(UBI was designed to prevent outcomes like these, btw - it’s too bad we didn’t do it when we had the chance.)