If even Trump was so afraid of the ocean that he couldn't send disaster relief to Puerto Rico, how would a slave ship be able to touch all that water, eh?
At some point we just called this eugenics, but then someone committed one of the greatest atrocities of all time, and now racist can't even be openly for the murder and sterilization of large parts of the population anymore. Because of woke.
I think it's just that on the internet, unlike in real life among people in a social unit, there is no such thing as a maximally extreme position. You can always look for, and eventually find, a more extreme view.
Just for balance, I can see how you could think shipping slaves from Africa to America via the Pacific and then the North Sea (of all places?) was unlikely. Maybe this person just isn't aware of the Atlantic Ocean.
Clearly slaves were shipped from the horn of Africa through the Suez canal. They then offloaded them in Nice France and flew them over to the US on C-5 Galaxy military transport planes.