That was well before the CDC and surgeon general were telling people masks are bad for you don’t buy them. The masks were long gone by then.
No, this is specifically addressed in the SSC piece. The CDC has been against masks for many years; their advice on masks this year was the same advice they've always given. There is absolutely no reason to believe they put any further thought into it than that.
White lies are still lies that cause people to lose faith in any advice you might have.
So it is not that the CDC was malicious / selfish / conspiring. They did what they believed was the best policy response. Even if we know better now that they should have just published instructions on making community masks and advocating their use.
> nobody was willing to run a study where you exposed half the subjects to a virus without any protection
Running the studies is effectively impossible due to ethics constraints. The CDC were probably lying about their reasoning because if you put all these facts together the CDC would not ever be able to take a position on countermeasures until it was clearly too late. I dunno what their idea of Disease Control is for pandemic, but a little bit of "balance of probability" thinking probably happened.
Even if we'd discovered masks were a complete waste of time, the cost-benefit of everybody spending $10 for hastily sewn cloth mask was clearly in favour of recommending the idea. We've had entire economies parked up, I'm sure the labour could have been found to do some knitting. As projects go it would have been a very productive use of time. They just didn't want to disrupt the supply of medical masks and showed a rather dire level of panic and unpreparedness.
But, the reason there weren't rigorous studies supporting mask usage was not because they don't work, but because nobody was willing to run a study where you exposed half the subjects to a virus without any protection just to prove that masks would help the other half. It's the same reason there aren't any double-blind studies proving that parachutes help you if you fall out of a plane.