Science isn't instant, it takes time to work things out and come to accurate conclusions.
Don't mistake our governments incompetence for science, I think the clue you should be looking towards is what do doctors and hospital staff wear when they don't want to be infected during the course of their everyday duties without even the presence of Covid19? But then I don't recall there being a virus that killed somewhere between 0.5% and 1% of those infected by it before, or cutting a swathe through our available ICU bed totals
Any mask is better than no mask, however ineffective according to the science.