That's what I hear, but personally, I don't buy it. When I fill a sink with dish soap, I don't want to see just water and no suds. I want to see lather when I shower; clear water doesn't cut it. When I wash my hands, the soap foams up. So I don't want any less for my clothes.
I want foaming, billowing mountains of suds. ;)
Way back when I had a job in a restaurant kitchen. One of my jobs was washing pots, and practically the first thing the chef told me was to put the detergent in the sink after it was filled, not during. His rationale was simple and quite obvious: Soap that is floating on top of the water, is not in the water working on the dirt.
The same is true of laundry detergent. The purpose of detergent isn't to make pretty bubbles. It's to break the chemical bonds between the dirt and your clothes.
Suds are simply a side effect of the fact that detergent is hydrophilic (tends to be dissolved in water), and air is not. They don't actually accomplish anything—except, on front-loading machines like clothes washers and dishwashers, to place unnecessary pressure on the door that might damage it.