Vote for the change you want to see.
The Republican party got remade because trumpists showed up and outvoted the party elites. No reason it can’t happen for the Left except for laziness and apathy.
If all the progressives furious about the state of affairs now had shown up for Sanders in 2016, I doubt we’d be in this hellish timeline. Sadly, he needed the young progressive vote to show up.
The black voter enjoyed a heavy Republican bias for nearly a century, and suffered much of the same treatment (GOP treated them as a captured constituency, Dixiecrats suppressed their turnout with fraud, incarceration, and terrorism).
By Kennedy, the northern Dems were embracing civil rights not as an electoral strategy but a labor organizing strategy. The vote was largely split, with black voters biasing by party in individual regions rather than as a national block.
It wasn’t into Clinton - when Southern Strategy Repubs had fully purged their party of black voters - that the trend was fully reversed. That wasn’t a decision by the NAACP or the median black voter. It was a Nixonian gambit. Black voters were viewed as a handicap. Appealing to fascism was how you obtained a majority in American politics.
Reagan, the Bushs, and then Trump seemed to further this theory. You’ll get two white voters for every black voter you lose, by being the most racist candidate in the ticket.