The pandemic seemed obvious in February; I know dozens (myself included) who bought masks and supplies long before the run on stores, long before even the USG was lying to people telling them not to wear masks (to preserve the supply). The briefings were around then. Were I a gambling man, I too would have shorted airlines then, and I wasn't in any of those private briefings.
The abuse is when they trade and then pass laws affecting the industries. A lot of kerfuffle has been around the covid briefings, but they didn't get anything an observant outsider couldn't see as well.
It has to be nonpublic information to be insider trading.