What tech ppl can do with that? Hm... probably go to teaching. And teachers please stop insist on studying boring classes and especially stop claiming History is not boring. Please, teach (give) Liberal Arts and nothing else and I believe most of that massacres will be gone.
There is no magic fix. It's a matter of changing minds 1 person at a time and getting the right politicians elected that will do something about it. They must be from both parties and can't be at extreme ends of the issue.
The bigger problem is that I don't think any one really knows what to do about it. That's the first step. Understanding where to start so we can fix the problem.
I say that because I live in a country where it isn't easy to get a gun unless there's a reasonable need for it. We do have stabbings (that one is harder to work around). But shootings are far rarer here than in the US, and mass shootings are nearly non-existent. Nearly all gun crap here is gang specific, and we just let Darwin explain the end result of that.
Gun play happens here, but not nearly every other day as the US seems to be dealing with.