To be fair, Beverly Hills isn't quite as squeaky clean as popular media would lead you to believe. Parts of it are extremely nice, of course, but it can't help but fall prey to the general sketch that encompasses most of LA county
That's to say, every society has its discontents who take their anger and frustration and discharge it on innocent civilians. Some societies manage their mentally ill people better than others. We do a pretty pitiful job at it.
Stabbing is harder than shooting people, so mass stabbings exist, they just can’t happen as often or do as much damage as mass shootings. Guns are just incredibly convenient and efficient for doing harm. Stabbings takes effort, which is why China’s homicide/suicide rate is lower than the USA’s, even if binary thinkers like to point out that it is still non-zero.
Mental illness as a culprit is a pretty tired explanation of these events. Statistically, mentally ill people are far more likely to be victims of violence than to perpetrate it, and in many of these events, there is a clear lack of diagnosable or observable illness to begin with. Besides that, even if you don't believe the numbers here, it's possible to improve mental illness treatment and legislate gun control responsibly, it's not an either-or thing. TLDR "Mental illness" is a very tired, very poor explanation for the phenomenon, not even to mention it perpetuates and encourages stigma.
> Statistically, mentally ill people are far more likely to be victims of violence than to perpetrate it
I think this is one of cases where a broad label like "mental illness" obscures more than it clarifies. There are some subgroups of people with mental illness (schizophrenia, bipolar, antisocial personality disorder) who are more likely to commit violence than others, especially when combined with substance abuse. But of course that fact doesn't generalize to all people with mental illness.
You are well-intending, but don't do that for factual information. I have seen discussions derail because of hallucinated parliamentary history; and the concept of truth became irrelevant.