Missouri, where the movement started, is the most glaring example. Trump won it by 18.5, doubling Romney's margin because his tough on crime message resonated with working class whites scared of those riots leading to a spiral of violence.
uh, what?
Missouri voted for Trump because Missourians are very receptive to populism, and Trump's 18.5-point victory came from running up huge margins in rural areas full of working-class whites and single-issue abortion voters. Ferguson, where BLM started, is in the middle of suburban St. Louis, which had no substantial swing from 2012 to 2016.
To be fair you could argue that St. Louis
should have trended D in 2016 much like cities elsewhere in the US, but didn't because of BLM cancelling that trend.