There is a HUGE difference between something not being God's ideal and something being "wrong" - in the sense that it could have been done differently. Let me use my own life as an example, first.
There are things I do that are not according to God's ideal. In a vacuum, they are - each and every one - "wrong". There also are things that my wife does that, in isolation, are "wrong". I flat out refuse, however, to insist that she change those things now - and I refuse to nag her and publicly say that she "should" be able to stop right this instant. As long as she (and I) is sincere in her heart and is trying to change, I accept fully her current ability to live the best she knows how - despite those areas where she still falls short of her own and God's ideal. She is who she is, and I love her dearly and unconditionally. I don't apologize for her, privately or in public; that would be judgmental and even more "wrong" than her weaknesses are in and of themselves.
An historical example:
Why do we assume that the early Church (meaning its living and breathing members, NOT the impersonal organizational entity), had to have been able to have our current racial understanding and acceptance - and why do we feel the need to apologize for them? Merciful heavens, they sacrificed and suffered in ways that I'm sure would have destroyed me. Just because they couldn't rise above their racism, why should we condemn them? Why should we insist that God should have MADE them do what they couldn't do - be who they couldn't be - and why do we assume God isn't crying over our own inabilities to live His law even while allowing us to stumble in our own weakness?
I believe, personally, that God allowed the Priesthood ban to exist and continue as long as it did specifically because He is so gracious and merciful and loving toward His children. I know that is counter-intuitive and sounds harsh when viewed from the perspective of those who were denied that blessing, but I desperately want Him to treat me that way, so I strive to allow Him to have treated racist but otherwise wonderful people the same way. "Blessed are the merciful, for they shall obtain mercy." I can't express how much I desire to obtain mercy, and if that requires that I quit demanding others be who they aren't ready to be - in this case, to quit demanding past leaders not have been racist or demanding that current leaders claim to know what they simply don't know (e.g., why the Priesthood ban happened) - then that is something I am willing to do.
Do I think the ban "originated" from God - that God revealed it to the Church? NO - unequivocally. Do I think God allowed it to happen without forcing revelation that the Church probably couldn't have handled? Yes. Do I believe that inter-racial temple marriage would have caused schisms in a church soon to be torn by the practice then cessation of polygamy - perhaps destroying it in its relative infancy? Perhaps, and I lean toward, Yes. I believe the ban was the product of racism, but I'm not sure it was "totally wrong" - in that I'm not sure it could have been different, given the composition of the membership and the time in which they lived. Just as a start, to avoid the ban, someone else other than Brigham Young would have had to have been the prophet, and I'm not sure the Church would have survived without "The Lion of the Lord" at its helm during those years. The more I study the more I believe that, even with his flaws and speculation and strong- and sometimes narrow-minded opinions, he literally saved the Church during those hellish years.The point is, I don't know if the ban was "wrong" in that sense, even though I think it was not what God wanted in His heart - not "right" from a moral sense. I just don't know. So I have no problem when our leaders say they don't know.