Did either Romney have an issue with the fact that for the first 31 years of Mitt's life he belonged to a blatantly racist religion?
As did Harry Reid and Mo Udall, but I don't see you talking about them.
Mormonism isn't blatantly racist. That picture says it all. Some of the founders of Mormonism may have said some racist things, but that doesn't make all Mormons racist. This picture is just further proof of that.
The issue is not with whatever anybody said but with the Church's position (until 1978) on what, exactly, Black people were.
The Mormon Church's position that was repealed in 1978 just barred blacks from serving as clergy.
Their reasoning for it was rather...interesting.