Firstly, your video is too long for most people I would guess.
I am not a Southerner, but in South Africa we have a few similar problems.
We had a system called Apartheid, essentially similar to Segregation in place here until quite recently. Some blacks, such as the leaders of the Homelands and traditional leaders, profited handsomely from the old regime and often tried to maintain their power (unsuccessfully) as Apartheid was dismantled. Likewise most wealth and land is still concentrated in white hands. The whites tend to feel that when Apartheid is discussed, it is used as a weapon to belittle their ancestors or to score political points in the present. Blacks feel that transformation and black empowerment has not gone far enough and often blame all their problems on Apartheid. This makes Apartheid a difficult and highly political topic which whites try to ignore and blacks constantly feel justifies anything they want.
When the Dutch first came to South Africa in 1654, they brought along slaves from Madagascar, Angola, Indonesia, Malaysia and India (although they did not enslave the native Khoikhoi, but turned them into essentially indentured labour). They then formed a slave-owning society until the British took over (1806) and freed the slaves in 1830. British policy and rule, a heavy-handed response to a tax dispute and the belief that they had been insufficiently compensated for their slaves, led to a mass exodus of Dutch-descended farmers (Boers) into the hinterland in 1834 (the Great Trek).
There they formed two Republics which the British then subjugated in the Second Anglo-Boer War (1899-1902). The Boers initially did very well before superior British numbers saw them overpowered after the first year. The Boers then switched to guerrilla warfare for the remaining two years before finally surrendering. The British burned the Boer farms and forced their women and children into concentration camps where scores died, in order to force their men to surrender. 80 000 Boer troops held off and initially won against 500 000 British troops.
This has left the Afrikaans-speaking whites very proud of their ancestors and heritage and makes them feel like victims of Imperialism. (Similar to Southerners history of losing the American Civil War and Sherman's march to the sea, only worse)
Because the Afrikaans population was predominantly (but not solely) responsible for Apartheid, Afrikaner flags and symbolism have become associated with Racism. This has led to the fact that the Vierkleur flag of one of those old Boer Republics has become the equivalent of the Confederate Flag in the US. It is considered a flag of heritage and sacrifice by Boer ancestors, but seen as a racist symbol by others.
So I have a lot of sympathy to Southerners who struggle with a divisive history of Segregation, who are unsure how to address it in the modern world. Who feel their heritage is belittled and brave ancestors insulted because of how a few Racists use their flag and have to fight off calls to remove it even from war memorials. Who feel like they are the victims of an Imperialist power that burnt their homes and crushed their independence, yet aren't allowed to properly celebrate their ancestors without being branded racists.
Apartheid was a crime, as was segregation. But that does not mean it must forever define a region, forever leave one group branded as Racist, prohibit them from celebrating the deeds of the departed or their history. This is patently unfair.
As to your questions:
Whites are blamed for slavery as it is easier than addressing the full scope of the practice and dovetails nicely with modern arguments of income inequality and racism.
All wars are about Class as it is about who has what and trying to keep it or seize it.
If the South won, they would probably have ended slavery themselves by about the 1880s as Brazil did. This is because they could not replenish their stocks from Africa due to the British ending the slave trade and the freeing of slaves by some masters and economic factors which made wage slavery cheaper than actual slavery.
The South, being dependant on Cotton which was exported to the Lancaster Mills in England, would likely have become a satellite state of the British Empire. There would also probably have been more wars between the CSA and the USA as they both expanded and perhaps they would have taken opposite sides in WWI, as the enemy of my enemy is my friend (Probably Germany, USA, Austro-Hungary vs Britain, Russia, France, CSA)
