The belief in the existence of a super-race (or whatever term Hancock uses) is dubious. While the idea on its own may seem harmless, it opens the door for racist idealogies. Everything has to be taken in context, and crackpot archeologists have been making this argument for ages in order to justify later arguments for eugenics.
I know it may appear that Hancock questioning the established historians and “big archeology” is above suspicion, but it is done in an unambiguously dishonest way. He refuses to acknowledge sound logical arguments put forth by multiple well-respected sources and hand waves things away as common sense. Essentially, he is frustrating because his arguments muddy the waters of logical discussions and introduce doubt in a community that certainly does not get paid enough for this shit.
The survivors of the cataclysm that brought their advanced knowledge to the ancient peoples is the super race.