Well that is in a completely different category than "lead", now isn't it?
Although I don't remember the "massive upheaval of lifestyles" suddenly happening at the beginning of June last year, is that your recollection of events?
To be clear, I wasn't supporting the hypothesis that lead exposure explains 2020, only pointing out that large year-on-year jumps in crime rates are almost irrelevant on the long trend. The Bay Area homicide rate went up 35%, but it was still lower than 2012 and all years prior to 2009.
That didn't really affect a lot of lifestyles. There's some economic evidence it caused people to stay home more (which had the result of reducing covid deaths) but they were already doing that.
A possible reason everyone was free to protest was they were unemployed.
Although I don't remember the "massive upheaval of lifestyles" suddenly happening at the beginning of June last year, is that your recollection of events?