Wow. So you
1) acknowledge that there are marginalized groups. That's good.
2) acknowledge that there are people who say "if you put me in a position of authority, I will help those people."
BUT
3) You view that as a threat (the blackmail part)
4) because you... want those groups to be forced out of society?
But saying "well, I don't want to be forced into voting for those people!!" is acknowledging that the system currently actively oppresses those groups and you don't want to help that group because...someone made you feel bad.
That is okay?
And what about politicians who threaten you with fear? The ones who say they'll make sure that marginalized groups stay marginalized? You're just as "nope, not gonna vote for them either"?
Since it's the same sort of emotional manipulation going on, but instead of the fear of being exposed as a bigot, it's the fear of that group being made equal to you.