Just linguistically, 'strange' is an ambiguous and even relative term. Many of the things in quantum mechanics or biology we may think strange, and for different reasons, but those things may still be true, though it seems to me that Shermer's use of the word here may be interchangeable with 'false.'
meh, he is giving a presentation, not writing a philosophical treaty. Strange would seem apply more to frameworks that lack substantiative proof, or a corpus of empirical evidence and logical evidence to back up their claims. His talk is more about human heuristics and cognitive fallacies than " truth "