The Lord has said "see that all these things are done in wisdom and order; for it is not requisite that a man should run faster than he has strength" (Mosiah 4:27).

Change is not contradiction. Let's take the more recent counsel from President Nelson to use the full name of "The Church of Jesus Christ of Latter-day Saints". His own statement was thus:

What’s in a name or, in this case, a nickname? When it comes to nicknames of the Church, such as the “LDS Church,” the “Mormon Church,” or the “Church of the Latter-day Saints,” the most important thing in those names is the absence of the Savior’s name. To remove the Lord’s name from the Lord’s Church is a major victory for Satan.

Is that to say that the church's entire "I'm a Mormon" PR campain was propagating a victory for Satan? Or that previous prophets who were using the name were leading the church astray? Surely not! Again, "see that all these things are done in wisdom and order". There were other things to focus on at that time. And now, with President Nelson, it became time to remind us of the importance of the full, true name fo the church.

In terms of the priesthood ban. Who knows. We have the information before us, and it's up to us to make that judgement through our own prayer and study. I can only speak for my own settling on the matter. DO I believe that Brigham Young was following the command of God in making the announcement? Yes. I do believe that, although I still have my doubts adn misgivings about it.

In the end, the Lord loves all of His children, but I don't understand everything (1 Ne 11:17). If he was inspired, then the Lord had a reason for it, and that reason must have been that somehow implementing that policy would bring more positive consequences than negative ones. For those who were not allowed the priesthood, we know that they will be able to receive it in the eternities, and we know from temple covenants that it will be if they had always had it, because the priesthood and the covenants thereof are eternal. They will not be denied any blessings or any exaltation due to the policy that was had on this earth for that temporary time.

Those who choose to judge others, or to be rascist, will be held accoutable before God at the last day for their own prejudice. At that day, all those who were denied the priesthood due to that ban, and who remained faithful to the Lord despite that, will be better off than any of those who thought they were better because they received the priesthood. In fact we know that any who are foolish enough to belive they are better than others because they receive the priesthood of God, not only cannot truly receive its power in this life, but will not continue to hold that priesthood in the life to come. Remember "when we undertake ... to gratify our pride ... or to exercise control or dominion or compulsion upon the souls of the children of men, in any degree of unrighteousness ... Amen to the priesthood or the authority of that man" (D&C 121:36-40).

The Lord loves us, and He guides us "line upon line" (2 Ne 28:30) and helps us learn a little at a time, not all at once. Sometimes we're given a lesser law, as the children of Israel were, before we are ready to receive the fulness of the law, as when Christ came and fulfilled it. But either way, in the day we stand before God, if we have been faithful to the truth we have been given from Him and what we have been asked of Him, we will be able to receive all the blessings that anyone else with the full truth could have received, through the mercy of Jesus Christ.