I have the impression that (although I did not check for data beforehand to confirm my assumptions) that gun violence is very low in developed countries, with the USA being the outlier.

I believe the overall positive employer-employee relationship in Europe is much more of a product of legislature and cultural norms, than the threat of violence.

It's definitely not related to the population's gun ownership ratio. I would say gun violence is probably comparable with our European neighbours. It's just way lower compared to the US.

Also, from my experience, there is not a clear trend whether companies in Switzerland want employees to keep working or if they just let them go during the notice period. I've seen many examples of both.

Even in US, it's not a strict rule. I gave my notice more than a month in advance and retained access to all employee spaces (both physical and digital) until my last day. Coincidentally, I own enough guns that describing it as an "arsenal" would not even be an embellishment it usually is.

At the end of the day it's more about culture (i.e. people's expectations of what is normal) than any objective factors.

Puzzled by why anyone would downvote a pure question. Wide distribution of guns is an obvious commonality between the US and Switzerland; if that's offensive observation please let me know why!