I fully admit that JHP bullets are hands-down the best defensive ammo choice. That being said, I wish law enforcement agencies would publish what types of rounds were used in criminal assaults and homicides. Gang related shootings are the most common criminal uses of firearms, unless you're in a jurisdiction that still considers suicide to be a crime (yes, that was a thing for years).
In my career as a Patrol Officer and Supervisor, I was directly involved in hundreds of gang-related arrests. Virtually all of the criminals we found with loaded weapons were using the cheapest FMJ ammo available, unless a gun was still loaded with the original rounds that were in it when it was stolen. If gangbangers are able to kill so many people with various types of FMJ ammo, it obviously must be capable. Wadcutters may not be the best, but I'm sure they can get the job done.