They want him to wear a mask to lead by example. And to counter his earlier statements that a mask makes him look weak, and that the whole coronavirus thing is a hoax to make him look bad, which have helped create legions of militant, anti-mask, cult members who throw literal temper tantrums when told they have to wear a mask.

But yeah, I wouldn't expect you to get it either.

Furthermore, there is some evidence that a mask affords a level of protection to the wearer. Certainly not foolproof and the primary reason is to protect against infecting others (also not foolproof), but also not worthless.
[Post edited by BocaHoo91 at 07/12/2020 07:27AM]