When you think about it “lizard brain” does kind of have the stink of human supremacy to it. I bet it even came out of that era of fascist pseudoscience. Not that I gave that theory much credence anyway, as I always used a more computer-oriented tree model for that sort of thing. Your brain stem is the root it has ultimate power but only does the most important things (as it would constantly override stuff if it didn’t) while the more specialized stuff happens out in the distance where it can do some more radical stuff without disrupting the entire process.