POTUS doesn't want to create a rush of people going to the doctors to get the cure, when we are trying to mitigate illness and verify actual current covin tests. They are distinguishing between who has a true diagnosis of corona virus, and who has the flu.
There is already a rush for the hospitals and doctor visits.
The cures will interrupt that process of figuring out who has corona first and bog everything down, even further preventing the cures.