You can actually have both idea's be the truth. Like in "Westworld" they didn't become sentient until they programed them to fill pain inside, maybe that along with a internal sense of superiority is a key element in making the robots work. You also have something like Section 31 around which allows the humans to not always embrace their darkness because they know, maybe like a instinct, that good will always win out because they don't always have to do horrible things to get their way, yet things keep working out for them.I like to think people are the same as ever, they're just taught from birth that they're superior and so they believe it. It adds kind of a dark edge to the squeaky clean Next Gen universe.
Jason