Firstly, slavery within the parts of Africa the slaves were coming from was usually much more bearable than plantation life. Chattel slavery is a completely different institution in that regard.
Degrees of misery are debatable and a bit out of scope. Suffice it to say, all buyers on sellers on both ends of the ocean knew what they were doing and used whatever mental gymnastics/rationalization they needed to feel at least okay about doing it.
First time I've seen someone complain about NI sets. I understand your whole "it's determinism" point but it'd be retarded to say we should give France and England the same opportunities about navy. The NI are a way to illustrate a nation's main whereabouts and achievements in history, I think they're very welcomed.
You're claiming that a 200-year landlocked Great Britain should have access to some of the best ships in the world, while France that conquered India + owns 2/3 of the western hemisphere should be weaker on a ship for ship basis.
And you're claiming that so strongly you'd insult people for the notion of refuting that!
If you want to make NIs illustrate achievements in history, make your position coherent and assert that NIs should happen as a result of historical achievements. Quoted name-calling is comically ironic because the stance isn't coherent .