The view in a mirror changes as you move your head from the inboard to the outboard position angle inside the cab, not so with a small tv monitor, you just get a "flat" view, this ability comes in handy when backing up and watching the rear of the vehicle swing. Also, the additional side view "monitors" in my opinion, would add to the light clutter in the cab at night. That's why I prefer glass outside mirrors.Mirrors are archaic. Time to move on. “TV screens” will allow for significantly better low light/dark visibility, for example, and can completely eliminate the blind spot (though I admit that properly adjusted mirrors also eliminate the blind spot, no one seems to know how to adjust mirrors properly any more.)
I doubt the equally archaic US Government will change its rules in time for the Cybertruck, however, so you’ll probably get your wish for real mirrors.
From a cosmetic point of view, I see where you are coming from ditching the outside appendages but a driver has to see outside quickly and sometimes you don't have time to fiddle around.