My personal theory is that they don't want to learn about 'the reality of slavery' because, if they do, they start having to come face to face with the reality that slaves were alot better off in America than any other location.

Arab slave trade? Hello, castration. Central America? Worked to death. Haiti apparently turned into an absolute shithole after the Haiti revolution, despite being one of the richest islands in the Caribbean before hand...

America is the way it is now because they did this weird thing like... keeping families together, or importing women as well as men, allowing them to actually have families and independent side businesses, manumission, not working them to death, and a bunch of other things that are a little bit awkward to learn about when they want to paint a picture of abject horror and misery.

Granted, alot of this stuff is hard to learn about because it's so sparse online, likely on purpose. The last time I had to go researching on the matter, it was very thin on the ground. I'd love to find a reliable source on the death rate for slaves in Central America, for instance, but... meh. I'd have to muster up the energy, and debating people on this stuff is guaranteed to drag straight into the mud.