I think if those were the underlying factors we would've seen a rise in the homicide rate earlier than immediately after the beginning of the pandemic.
I think it is a multivariable thing, especially when you are looking at different municipalities and their respective crime policies. A lot of the places that top the list have had rising homicide rates over the past decade from a low around 2010-2015, with the national rate reaching a local low in 2014 before climbing from there. To me it could suggest that populations were coping (poorly) for a while before the pandemic broke the camels back so to speak.