No, the reason politicians don't take black voters seriously is because no matter how many times they do absolutely nothing for black people, they can pretty much guarantee they'll get 60-80% of the black vote.
Every election season black people are told how important it is to vote, but we're never told what we're getting in exchange for our vote. Obama got over 90% of the black vote running on a campaign of hope. Not investments in black neighborhoods, not investment in black education, not a promise to tackle the systematic racism in all levels of the private/public sector; but hope.
I've voted for free, and I'm not doing that anymore. If a candidate wants my vote, he either has to directly address either reparations for African Americans, or give a specific amount of money he's going to earmark for the creation of black owned and operated businesses. Without that I'll keep my black ass home on election day.