Agreed, no matter how clean it looks after snow foam and rinse, its always a hand wash with the lambswool mitt. Or else you'll be rubbing some small particles into your paint for sure and causing swirls.
if your not touching it .. how can you rub small particles into your paint ?
He might mean if you were drying the car off after just no touch washing, without doing a bucket wash, which, if that was the case, would most likely result in pressing/rubbing dirt particles into the paint, causing swirls. Most swirls are inflicted at the drying stage.. But if you aren’t drying it then no issues, apart from potential water spots if hard water and no DI filter.