Is it objectively in inner-city blacks' "best interests" to keep voting Democrat and remain mired in poverty for generation after generation?
Do you really think ideology is the solution to everyone's problem? Do you believe your enemy's ideology is itself the cause of everyone's suffering?
While we're sitting here arguing about liberals and conservatives, Democrats and Republicans are either ignoring us or outright raping us. They give us the minimum amount of attention, then they directly target us with punitive laws and regulations for their own personal enrichment.
Going more extreme, and demanding a unified front of all Republicans or all Democrats... will only get you more of the same. Black people voting solid Republican instead of solid Democrat won't help them, just like how a state voting Republican all the time hasn't helped them solve their own perpetual issues.
If everyone voted Republican (or Democrat) 100% of the time, we'd still be fucked. That's because we have fundamental cultural and political problems that prevent us from working with and responding productively to objective data. Everything is about appearances and personal gain. "How will this look if I do X". "How will this affect my reelection campaign?" "Will Evil Corp support me next time around if I do Y?" Next thing you know, you're an ineffectual politician good at only lining your own pockets and your people continue to suffer.