What an interesting mix of cultural understanding (references to the injustices of period-appropriate-ish black-slave treatment) and yet still blatant racism ("Only Asians, being a superior race to these black men, can normally cultivate.")
The line in question is, "Because our culture and race did not assimilate with the culture of cultivation," yes?
The pertinent question is, why is the word "race" in there at all if it's only talking about culture? How is it even relevant? I could see it if it's just, say, bad translation.
I'm specifically talking about what you said in the parentheses. Nowhere in the manhua is said that only Asians can cultivate because they are superior to the other races.
The point that I am raising is that regardless of the race of the slaves, both the westerners and their slaves in this manhua did not cultivate and that is due to the difference in cultures.
"Your master is a good person inside" - Obama
my take away: Your master is a good person inside, But your master is an even better person INSIDE ( ͡° ͜ʖ ͡°) ( ͡° ͜ʖ ͡°) ( ͡° ͜ʖ ͡°)