I don't think Karen Hunter could find a (Black) guest willing to appear on her show to claim opposition, but they should have tried to find an elected official or judge who opposes it to speak.
They would be able to answer why a debate exists over the issue. And why they would use their vote to block it.
In terms of the study, the lady on the bottom of the screen gives the direct answer. And I'd add that because political opposition exists, the proponents are going to have to present the best possible case to get the votes needed.
*The lady at the top right corner is a former Miss America