OP has 3 other threads on the same page of this board which are all suggestions for mechanics. I wouldn't say they're trolling by suggesting another mechanic, especially when it's one that is mentioned in dialogs and exists in the lore for this game and previous titles in the franchise.
You made it racial, when in the context of the game it would not be. For the majority of history it also was not racial, but punitive or a matter of convenient supply. One of the most common methods of enslavement around the world was exactly what we've seen in M&B, which is taking prisoners of war. This was even a source of slaves that arrived in America from Africa, as different warring groups would sell their captives to European slave traders. No race has a monopoly on being victims or perpetrators of slavery. The implication that if there were (more) black people in Bannerlord then it would justify a slavery mechanic is race-baiting, and not tolerated on this forum.
There are so many replies that have tried in good faith to educate you on the matter that I won't be deleting any of those posts so far in the thread. I would like to remind people that insults aren't educational, and to refrain from making the situation worse.
He may or may not be, but I certainly am. Are we going to go from generalizations about slavery to generalizations about Americans now?