Tyre damage according to wheel

During the recent rains in Victoria pot holes appeared in the Calder Highway that were big enough you could fish in. I hit one of them hard enough to pull over to see if there was any damage. There wasn't but there were four cars within 100 metres of me changing wheels. The common denominator was large wheels and low profile tyres, three of them had 18-inch mag wheels and the other had 18-inch steel chrome wheels and all had low profile tyres. I have standard issue 15-inch steel rims, which were not damaged. A few years back I was helping my son buy mag wheels for his car and the salesman did say at that time that 18-inch mag wheels were susceptible to damage. Are the larger wheels more prone to damage or is it the lack of give in the low profile tyres or both?