Actually, the first statement is correct. SARS, which emerged in 2003, was determined in 2005 to be transmitted by aerosols. Masks do not filter out aerosols effectively enough to prevent transmission. The NIH and CDC knew this about SARS which is very closely related to COVID-19, sharing about 88 to 90% DNA.
Get a small unventilated room. Either you or somebody else smoke a couple cigarettes in it. The smoke will accumulate in the room, floating in the air for quite some time. Virus laden aerosols exhale by somebody with COVID-19 will do the exact same thing.