'Upgrading' to skinny tyres pointless for London commuting

A tyre that presents a larger contact patch gets less punctures despite encountering more flints? would live to know the science behind this.

Skinner smaller tyres have less contact point so says 80kg will be on that tiny area thus more likely to get sharp debris embedded.

Wider tyres - more contact point, but weight spread around that contact point thus less likely to get sharp debris embedded easily.

I hope I explain it properly.