I think slavery would have ended on it's own eventually. New technologies would have made slavery obsolete.
It should have never been a part of this nation. Of the 13 original states, Virginia and Georgia, were the only two states who refused to end slavery when this nation was founded. Had they went along with the rest of the states, slavery would have illegal in this country from be beginning.
We were going to war with the world's biggest superpower for our freedom and we needed to have all states on board or they would have most likely fought on England's side.
There is so much in the history of this nation that is just not taught because it contradicts the narrative the left wants to promote. Like how prior to about 1650 there was no slavery. It was all indentured servitude. The difference is ownership and duration of service. An indentured servant is not "owned" by the master. Much of the indentured servants from Africa were indentured for life but not all. And a lot of people immigrated to America by indenturing themselves. This is how the paid for passage on the sailing ships that brought them here. Those servants worked for a period of time and then they were freed.
When an indentured servant had finished their servitude they were typically given 40 acres of land and a mule.
In 1650 a black man named Anthony Johnson when to the English court to sue for "ownership" of a slave named Casor. He won the case and that changed indentured servitude to slavery.
There were free blacks who voluntarily fought in both the Revolutionary War and Civil War (on both sides).
There was at the highest point about 300,000 slave owners who were black.
There have been politicians in the federal and some state governments who were black.
The left does not want that information to get out because then it would be a little harder for them to create the oppressed/oppressor ideology needed to push Marxism.