This is an old-wives-tale and needs to be divorced along with the old wives that spread it and the M-16 x 5.62 that it rode in on. American soldiers don't shoot to wound, so why should their combat rifle? The idea that Muslims or communists are going to waste manpower on caring for the wounded is ludicrous. The one main reason we are fighting these people is that they are animals. They don't care for their casualties, their countries or their societies.
When one openly states they have never seen combat, it is not necessary to keep shooting...lol...
The old doctrine I was taught in ROTC was that you shoot to wound. That way you take out of action not just the guy you wound, but all the people who must care for him
In current fights, a wounded enemy is abandoned by his side, and cared for by US. Thus every enemy wounded, but not killed, costs the US multiple people needed to care for the wounded enemy. And new rules preclude our doing anything to get useful intel out of him