I don't think you're seeing the bigger picture here.
I live in a mostly red state; most people who protest vote don't do so because "the better candidate is gonna win my state already".
I hate to say it--because right-wing pundits have completely polluted the term--but this is "virtue signaling" at its finest.
We'd have to get all black people to vote first.
Even when Black people turn out to vote in record numbers, there isn't a significant shift in political viewpoints among the left.
Mainly because there isn't a consensus on what Black people in America want any given time.