Now in fairness this was before airborne transmission was as well established [1]. The Tweet came 45 minutes before the LA Times article documenting airborne transmission at a choir practice. But still -- it is unforgivable that they said, "Fact: COVID19 is NOT airborne" rather than saying, "We don't know."

And it really shows the dangers with Youtube's policy of banning coronavirus related videos that contradict World Health Organization advice -- there is no magic pixie dust that makes the WHO an infallible authority, and like any bureaucracy, they are subject to increasing rot and incompetence over time.

[1] Actually, to be more specific, it seems this whole "airborne" versus "droplet" transmission distinction that the WHO was adhering to is a false dichotomy and that it is much more of a messy gradient than sharp distinction.