That sounds like an Urban Myth. So I googled it. The best results say wax your car. Keep it waxed.
Pam is oil based. No one wants greasy oil collecting dirt all over the front of their car.
Not saying Pam is not good, just saying it’s not optimal.
Pam is just for long trips on the Interstate, not everyday driving for the month they are swarming.
The bugs are very acidic and will pit your paint badly. I’d much rather have a oily film on the car that will wash off easily that have to get a new paint job.................