If you want to change something you have to work within the confines of what you're given. We can all sit back and idealize about what would be better all day but with the systems we have in place and a first past the post system is what we've got there will always only be 2 valid candidates. First past the post always converges on 2 candidates.
By abstaining you only tip the scale in favor of the worst possible outcome. The real move is insurgency into the system and placing favorable candidates.
Not only that, if a presidential candidate was to run a militant, pro black campaign, he/she wouldn't even make it past the primary as no major donor would back them and it would certainly alienate white and Latina (centrist/moderate) who significantly outnumber black people in America.
In addition to that, most policy and agendas are set and driven by lobbyists and donors. You can't expect politicians to cater to the average/common voters over their big donors. It's sad but unfortunately that's the game.
The choice are either black people pull together and financially back a winning candidate or vote for the lesser of two evils.
Hoping for some knight and shinning armor candidate, let alone one that will actually win the presidential election is a pipe dream
