Just watched that TMZ interview with Kanye. They were kind of meeting him half way with the Trump shit, and then he drops the slavery comment. lol
They were like, "Okay, it seemed a bit weird, but I guess we kind of understand it...". And then he drops the slavery comment.
To be honest, my first thought is, "what do you mean exactly?". It kind of sounds like something that seemed to make sense in his head, but he couldn't articulate it. Then again he could just be crazy. Either way you don't really know without digging deeper to see what exactly his train of thought is.