It seems to me like someone is designing these for the war zone in their head.
This all started with the bio-attack mode on the ModelX. Now we have bullet proof windows, armor plating, and sharp edges. What’s next a retractable Gatling gun? Will people bat an eye?
If you need a high rate of fire and are space/weight/power constrained, you might be better served by using a Gast gun design, like the GSh-23. You don't get to the same max rate of fire, but you also don't need to spin up the barrels or use an external power source to drive the gun.
