> there is no increase in disorder

The mobile phone created an occupation for people who would otherwise be on the street committing crime. It paced people, even common kids, adults, we commit much, much less crime than the previous generation, and even less in unreported crime (bar fights, revenge against a neighbor, etc.). The boomers used their hands!

But the problem is: If you follow the average strength and fight training of citizen from 1970 to today, violence should have been practically zero. It is much higher because some subsets have abnormally high rates.

You claim the average is going down. OP claims it’s going up. Both are right. Violence wins.