It’s not the gun that does the damage. It’s the bullets after they leave the gun.
Not to mention that if you’re using a semi-auto or even a full-auto, those ejected casings can burn a little bit if they happen to find their way down your shirt. ow, ow, ow, ow. I went to a one day class at Front Sight a few years back and some gal, thinking she was Rambette, came all dressed in black/white/grey camo with a matching tank top. A few 9mm spent casings from an Uzi found their way to an uncomfortable location. ow, ow, ow, ow.