They did not provide the context, which was misconstrued as lying.
Everyone did not need to wear a mask at first because it was not widespread enough for them to be effective for the general population compared to making sure medical staff who were far more likely to be exposed had masks. Masking by the general public at the very beginning was a waste of masks compared to just reducing the time spent in groups. It became effective as time went on and the mask supply ramped up.