I don't think you are going to see many of these people go back.
First, once lost possessions in the homes, but I doubt they owned the homes, I think many were living there on vouchers.
Now they are in places like Texas and some who wanted to work have people finding work for them and those wanting to remain a part of the (Great Society) want to remain so in a better piece of real estate than they were in.
Louisiana has lost some folks for good.
I'm guessing a significant number of them.