I've also heard it claimed that masks not helping was pushed because there was no peer reviewed randomized trials that showed that masks helped therefore the of

I've also heard it claimed that masks not helping was pushed because there was no peer reviewed randomized trials that showed that masks helped therefore the official advice was there is no evidence that masks helped. Of course there is no randomized trial evidence on the effectiveness of social distancing on long term reduction in mortality due to corona virus but different ideas have to hurdle different levels of evidence. This idea of different levels of evidence actually makes sense because some things have potentially high payoffs and very likely low costs. For example wearing masks would appear to fall into this bucket. This comes back into reasoning under uncertainty that someone else brought up in the thread. The medical community has had problems in the past because bad medical interventions typically impose high costs on patients so if they have little positive benefit then it can easily become a net-negative situation. So then you have a culture where anything that hasn't gone through an RCT with multiple confirming studies doesn't exist as an intervention.