Plausibility is a trap for the truth laid by lies.
Our conscious motivations, ideas, and beliefs are a blend of false information, biases, irrational passions, rationalizations, prejudices, in which morsels of truth swim around and give the reassurance albeit false, that the whole mixture is real and true. The thinking processes attempt to organize this whole cesspool of illusions according to the laws of plausibility. This level of consciousness is supposed to reflect reality; it is the map we use for organizing our life.
This is a large part of the academic profession: to make up complex, subtle arguments that are childishly ridiculous but are enveloped in sufficient profundity that they take on a kind of plausibility.
Rank beliefs not according to their plausibility but by the harm they may cause.