Lack of RCT is a crutch (in this case), the practical reason is that as hard as it is to get face masks now it would have been much harder if the entire population was scrambling for them in the early days of the pandemic and given the US size, purchasing power and worldwide visibility it would have made it more difficult world-wide - all Western countries did the same, de-emphasized masks as they were imposing a lockdown and are now emphasizing them when planning for gradual release.
The article claims to refute your statement by pointing out that "The CDC has been singing the same tune for the past ten years. Swine flu, don’t wear masks. SARS, don’t wear masks. They’ve been really consistent on this point. But why?" This text in the article has several links.
Seems pretty consistent with my point - if masks weren't believed to be effective they would not be recommended "if unavoidable" , a use / don't use recommendation is not the same as a scientific finding of efficacy - it almost always factors in an implicit cost-benefit analysis of exactly the kind SSC advocates for. Case in point - all countries are now recommending (and in some places legally requiring) masks and not because a bunch of RCTs were conducted in the last two months.
