Given the rise of racial hostility to free African Americans and the exhaustion of the anti-slavery movement in the early 19th century, was the "back-to-Africa" movement the best option for blacks?
This is, of course, a matter of opinion. We cannot know for sure what would have been best for the African Americans at that point in history. My own view is that the colonization movement would not have been the best thing for African Americans.
Some people might say that colonization was the best option. In those days, there was clearly no chance that white Americans were going to be willing to treat free blacks as equals. It was likely that blacks who were freed from slavery would be treated very poorly in the US (as indeed they were after the Civil War). Therefore, it might seem that sending them “back” to Africa would have been the best thing for them.
However, this ignores at least two important factors. First, this would have been impractical. In 1860, there were something like 1.75 million slaves in the United States. It would surely have been impossible to find and pay for shipping to send that many people to Africa. Second, and more importantly, it is not at all clear that the African Americans would have thrived in Africa. It is not as if they would have been returned to a society from which they, personally, came. Most of the slaves were, by the 1840s, generations removed from Africa. They did not know anything about how to live in Africa. It is not clear that it would have been possible to get them enough good land to live on and to farm.
Thus, while it may seem that colonization would have been the best choice for African Americans, it is very unlikely that a mass colonization effort could ever have worked well for freed slaves.