Huh? Lets see you trace MTG's legacy roots. If there are so few lost cause supporter, why do they sell so many Loser's Flags?
This is a tangent. The original point was about the voice, and it was one of numerous barbs aimed at Honest Abe by supporters of the Southern Planter Aristocracy. Everything aimed at Kamela comes from supporters of the Theocratic, Kleptomanic aristocracy known as Trumpism...
MTG comes from a long-line of rabble rousing Congresspersons on both sides of the aisle. If you go to MTG, then we need to discuss the likes of Omar and Tlaib who really have no precedents.
By the way, you don't see a lot of confederate flags anymore in the South. You kind of have to go look for them. You won't see them in the cities, the suburbs and a lot of towns. Of course, there are will always be some knuckleheads who fly the flag. Maybe you will catch a bumpersticker on a long drive on the interstate.
The problem with your thesis is the changing demographics of America. Cities like Atlanta, Dallas, Charlotte, Raleigh, etc. and the areas around them are increasingly not even Southern. The Southeast Atlantic seaboard and Gulf Coast are being filled up with Northern retirees. Furthermore, Trump's success in the Great Lakes region doesn't fit well into your argument.
No offense, but you seem to be stuck in some progressive time warp where you really want to believe the politics are exactly like 1962.