"The racism in the church lasted a really long time, from Brigham Youngs presidency through the early 1970's"
While it is quite true that early members, and even modern ones, were racist, the same thing could be said about the american founders. Are you going to leave america because the early leaders were more racist than Brigham Young (Thomas Jefferson had 175 human beings as property as he wrote 'life, liberty and the pursuit of happiness', by 1822 he owned 267 slaves).
Remember gab92 said:
I know it is in the past but it bothers me that they don't accept it as one of Brigham Young's many human mistakes and one of his prejudices.
And therein lies the problem. America has acknowledged that its racists laws were a mistake. The LDS Church has not. Racist doctrines are still in the Book of Mormon, which they claim is still the Word of God.
You see the Church tries to paint this picture that it is led by God and the practices of the Church are led by God. If they were to admit that the Church was wrong about denying blacks the priesthood and temple sealing ceremonies and everything else, they would undermine the idea that the policies they set in place are god's policies. That would free the members to think for themselves and question the Brethern.
How might that play out? Some might then say, "Hey they were wrong about blacks and the priesthood, so they might also be wrong about gays now." Every decision, policy and doctrine could then be questioned. The Church would be vastly different then. Some members question the Brethren now, but are seen as on the high road to apostacy, but if the Church admitted it was wrong, then it would not be out of line to think they might be wrong again.
So, this blacks and the priesthood issue that is supposedly "in the past" continues to impact the present in a very significant way, and that is why it matters.