Why would a shooter waste a shot, of any sort, on anything that looks like a vest/armor/,etc. Head shots or maybe belly or thigh shots will change the attitude of the miscreant in jig time? If one can’t shoot one might want to avoid starting a fight.
True.
Center of mass is the biggest, easiest to hit, vital target, especially in a chaotic, fast moving situation.
That said, if you can see an armor plate, you should, probably, try somewhere else.