The antonyms for the word "more postulated" are few and far between. "Postulated" means a proposition asserted as true without proof, and "more" intensifies the degree of the proposition. So, the antonym would mean less or reduction in the degree of the proposition. The words that came to mind include "less probable," "retracted," "withheld," "contested," "refuted," and "disproved." However, these words do not precisely convey the opposite meaning of "more postulated." Therefore, it is essential to use the right words in a particular context to express the intended meaning clearly.