The argument is a moot point, reason being if the Rig you wear is not a full ballistic rig,such as the CIRAS, you're not offered the same protection as say a simple plate carrier, like the Blackhawk type.....a simple thing that costs.......$200!!!......
It's the Ballistic soft armour that's offering the protection, I have the BALCS soft armour that now fits into my CIRAS,or the PACA soft carrier, which also can also hold Ballistic plates.
Many guys wear the Plate Carriers , with no soft armour under it, and what they should realise that their plates need soft armour under them ,unless they're Stand Alones, with the soft backing,as the impact from a 7.62mm will break their ribs, but the soft armour under a plate will absorb that impact, and redue that impact substantially.