Sure, there was and is political posturing with regard to pandemic countermeasures. The reassessments haven't been about learning how masks work but about how

Sure, there was and is political posturing with regard to pandemic countermeasures. The reassessments haven't been about learning how masks work but about how a particular virus spreads and the efficacy of various types of masks in various settings between parties of varying contagion levels. The advice also has to be grounded in practicality given current circumstances (supply constraints, rate of asymptomatic spread among vaccinated populations, etc)