Also stupid in the sense that not even EMT vehicles do this - they run at speeds that keep the patient alive (ie. stable vehicle, no rocking and rolling) and ..
FIRST!! You stop the bleeding. Clamp, strap, tourniquet, whatever.
Have you not taken a basic first aid course? Your friend is dead with you at the wheel.
Not every road is unsafe to drive at high speed.
And this all assumes that there are no corners, no traffic lights, no other traffic etc - that you can just point your car directly at the hospital and hit 120mph and sit there for 50 minutes straight with no interruptions.
If you plan to average 120mph for 50 minutes of driving (to allow for corners, traffic, etc) then you are approaching Formula 1 car levels of speed (they average 138mph across a race), but in a non-F1 car, on a non-F1 surface/track, and a non-F1 skilled driver.
If you need to go less than 100 miles, say 10 or 20 miles then the time saving of going over 100 shrinks by orders of magnitude so the benefits of going over 100 shrink too.
This does not sound like a reasonable argument to me.
Emergency vehicles are involved in proportionally more accidents and they have trained drivers.