1) President Trump got diagnosed with the corona flu
Yep
2) Best doctors in the US administer drugs based on best practice
"Best practice" for remdesivir:
https://www.bmj.com/content/370/bmj.m2924
Current practice Remdesivir has received worldwide attention as a potentially effective treatment for severe covid-19.
"Best practice" for dexamethasone:
https://www.bmj.com/content/370/bmj.m2648
RECOVERY findings therefore support use of dexamethasone only for patients with hypoxaemia, not those with milder disease. The data do not support use of dexamethasone or other corticosteroids in the outpatient setting.
"Best practice" for Regeneron:
Woops, there are none - it's an experimental drug still in phase 3 trials.
Yes, I can easily imagine doctors giving experimental drugs to their top-priority patient who has a "mild" case, cuz, heck, why the hell not?
3) President looks perfectly fine and healthy, continues to carry out his duties
Ya got me! It's true, he is every bit as effective at carrying out "signing blank pieces of paper and scowling menacingly at disconnected telephones" as he ever was.