Historians of the future will have been trained in the postmodernist university system of today.

The core tenet of postmodernism is that there is no objective truth, everything we see in the world is a societal/human construct. It's a pants-on-head extremist outloook that allows absolute insanity to parade as intelligence. It's reasonable to assume that there is at least some semblance of objective truth and argue about the degrees.