How do you know I haven't formed this view based on data? You're assuming I don't have any data.
If your guess is right, we'd see differences in the effects of Jim Crow depending on what part of the country people lived in. Well, do we? I don't know.
That's one, very obtuse hypothesis.
And if you're going to try and draw conclusions, then come out and say it instead of noncommittally leaving it up to our imagination.