I know this claim is made, over and over. But most of the "wealth" built up with slave labor was destroyed during the Civil War.
When you look at the Capital accumulated in the South, most of it was in the form of slaves. So, if you claim the wealth of the USA was created by slave labor, you are saying the wealth of the USA existed in its black population.
After the War Between the States, the black population only did a little more than feed itself.
Some more, but not huge.
Slavery was producing 72% of the total revenue for the Federal government in 1860. It had been producing the bulk of the tax revenue since the 1820s. Pretty much everything connected to government during this era was paid for by the slaves.
When you look at the Capital accumulated in the South, most of it was in the form of slaves.
My recollection is that it was roughly equal to 4 billion dollars in capital investment that simply vanished with the Union invasion of the South.