Please be my guest, if you can find month-by-month shooting and/or homicide numbers for NYC/Chicago/LA/other cities that have seen big 2019->2021 homicide spikes. I spent a few minutes trying, but this one the only one I could find nicely broken down.

The coarse yearly numbers tell us these crimes have increased, they don't let us see how they play out with regard to the different things that changed in 2020.

looking at just 2019-2021 is cherry picking. Look back to the 70s and 80s if you really want to see that our current "crime wave" is nothing more than a made-up crisis for pushing a law-and-order agenda.

Looking at a potential inflection point where a trend reversed, to try to understand it (blip? new trend? change caused by change in underlying conditions?) is not cherry-picking. It's being responsible.

"It was worse in the 70s" is "the climate is always changing"-level deflection.

"It was worse in the 70s" is not a compelling argument for a political platform - having nothing meaningful to say in response to new events is exactly what would help "tough on crime" un-nuanced crackdown politicians elected.