Here is where they were in late March, advising wearing them only if sick or coughing.
https://www.nytimes.com/2020/03/31/health/cdc-masks-coronavirus.html
I think a message of 'We recommend masks in public as they are used in many countries during high virus seasons, but we're short on them at the moment. When they become available, we recommend wearing them in public' without even mentioning the grey area of if they were effective or not. Opening up that grey area imo gave way for people to take it to a whole other level.
Just like calling things 'lock downs', etc., the communication and messaging from all sides in this has been abysmal. It's new and hard to pinpoint things, but a 'This is what we know, this is what we'd like to get to, and this is how we're going to, be aware that it may change' type of deal is at least honest and lets people know where things stand and the stupidity of people would have been at least maybe lessened.
Think about how well Jamie Pollard communicated the plans for football. Agree or not with it, he laid out the foundation for the plan, and left it up to people to decide based on the information available, including a back up plan with allowing for tickets to carry through to the next season. There weren't any committees with 17 point plans with sub-points etc. Just a 'this is what we're doing based on what we know, this is what you can do, and here's what you can do if you decide not to attend'. Most of the reactions iirc on here were 'That's reasonable' even if they didn't agree.
A lot of Europe was also on actual lock down and has just really started easing up. They're not full blown open and it's not gone from there. We'll see what happens as they open up more. I'd bet they see more cases/deaths. I was hoping it would wane off a bit like the original SARS reportedly did but that's not the case.