Also, they never actually lied, you can see the post here in some of the other comments, people were just idiots at the time and didn’t actually read the full post, just saw “not recommended for general public use at this time” and somehow took that to mean masks didn’t help. Instead of that they do help, but save them for the people in need, not general use. The post actually has a video in it that also specifies masks should be worn by medical professionals and other close contacts with the infected. Which is very much specifically saying masks do actually help.
But of course, at the time, the detractors wouldn’t link the actual source, they would just pick one sentence and “…quote…” it, completely removing all the context and making it look like it said the opposite.
Also it’s not like the idea of masks helping was ever in doubt among educated people. It’s literally been a go-to for more than a hundred years already. It was only the uneducated that needed to be told.