My attempt at a TLDR for this: Bayesian assign a probability to each belief in order to represent uncertainty but this is insufficient because there are multiple kinds of uncertainty: vagueness, approximation, context-dependence, and sense vs nonsense, knightian. And sometimes we humans make logical errors when we try to do bayesian inference.
Just my opinion: the concerns are valid but exaggerated.
Perhaps exaggeration is justified in order to get people's attention since most americans are still treating this as a normal election.