In the early example, you point out the risks of interceding, but in the later example you point out your contempt that administration didn't intercede sooner.

Yes, there are risks in interceding, these risks don't magically go away when someone is in an authoritative position, especially over adults. Police regularly risk their lives expressly to intercede and I fully believe that more citizens should do similar. Why, because police are always minutes away when a violent crime will be over in seconds.

I've literally seen a good citizen with a gun stop a violent crime more times than I've seen Police able to do so. I've also seen similar with unarmed involvements. Yes, there are real world risks, that doesn't mean you stand by and let society decay right in front of you.

There is a risk of citizen action rising and becoming the violent mob as well... this has happened for good and bad outcomes. That doesn't imo mean that you shouldn't try. This is just my own hot take... it doesn't mean I would be comfortable in any given scenario or that I expect everyone else to be... but I would expect more to do so and be rewarded (or otherwise not criminally charged for doing so) than seems to be the case in modern society.