There are talks already to undo the "stay-at-home" restrictions in some countries pretty soon ( e.g Austria, perhaps Germany) both for economical reasons but also to get "herd" immunity on the long run . But these will not restore air travel in a matter of weeks. .
There is also some civilization / economical models which might not survive this crisis. , The create need for superfluous items that extensively relied on air transport to exist. The flower industry is one of them for instance..
Ferrying people in and out of cruise ships is another.
One of the International Organisation I work for decided to cancel all meetings/ travels in 2020. and go for virtual solutions. There are many of such examples that might either not survive, or at least take a certain time to restart. They might individually be a small percentage of traffic,but all of these put together will also have an serious impact on demand.