>Again, CDC did not say masks aren't effective. They said we don't know if they are. This was and largely remains true.
Like I said, it was "true" only in the sense that "we don't know if parachutes work [to save you're life in freefall from an aircraft]", which is to say, it's criminally bad to communicate that as your advice, given the costs and benefits to the user. There was no great shift in evidence that caused the CDC's change in advice, only a change in which way they wanted to clumsily manipulate the public.
>"Has foreseeable negative consequences" != "is stupid," especially in emergency scenarios where you're picking between bad options and worse ones.
Correct, and the path they took foreseeably led to the worse ones rather than the mere bad ones. The few people who correctly saw through the CDC advice still hoarded masks, still made up for the non-buying of those who nobly held back (it only takes a few hoarders to exhaust the supply), and health care providers still saw the very same shortage ... it's just that now, they have to walk back the advice against mask-wearing and suddenly pretend the evidence became ultra-strong overnight, even though half the public has made the earlier statements their hill-to-die-on, and we missed a very large window in which we could have been advising people to make good-enough ad hoc masks.
In what world is that the less-bad outcome? Or somehow not foreseeable that the public might actually believe you when you lie about your position on masks?