Inbreeding makes people stupid? SO Trump won the rural areas where no one lives. They're all going to feel really stupid when they lose their farms due to Trump's tariffs.
The thing about blacks is they did not understand how prejudiced FDR was against them but he promised them money. They liked money way more than they wanted to stay Republicans. Republicans always have backed Blacks. But the criminal element among blacks hates whites and the blacks changed to being fatherless for the family. Candace Owens really articulates this for blacks.
I think your history is a bit confused, but again, you're a Mormon. You think Joseph Smith was talking to God when God told him to fuck little girls.
Okay, so the actual history. The GOP was great when it fought against slavery, but then they kind of gave up. It started with the 1876 election, where Rutherford B. Hayes ended Reconstruction in exchange for being granted the Presidency after he lost. It went on with the 1880 election, when the GOP realized they had enough votes in the EC where they didn't need to win the South and therefore didn't need to encourage black votes or protect black rights.
Still, the GOP did pretty well with the few blacks who were allowed to vote up until 1932. That's when not only blacks but northern whites realized that the GOP wasn't their friend, and we had 20 glorious years of no Repukes in the White House. When they did get in with Ike, they had to concede Democrats were right on the important issues. During that period, Republicans could still count on about 30% of the black vote for blacks who were allowed to vote.
Then came 1964. LBJ betrayed the Southern Whites by signing the Civil Rights Act and the blacks, now allowed to vote, swarmed to the Democrats. Barry Goldwater got 6% of the black vote, and it's pretty much been in the basement for the GOP ever since. 13% is a high water mark, but I suspect that's more to do with Trump's celebrity status than agreement with his policies.
(We are a stupid society that mistake celebrity with merit, for some reason.)
Of course, the downside of that has been 50 years of Republicans playing racial politics, starting with Nixon's Southern Strategy, going on through Reagan's whining about welfare queens, Bush's Willie Horton ads, and Trump talking about birth certificates.