It's bullshit. This net carbs BS was started by the Atkins Diet plan after Dr. Atkins sold his name, diet, copyrights, and trademarks to a corporation. The corporation perverted his diet to sell products. So in the name of net carbs they started selling "low" carb candy bars, muffin mix, pancake mix, and a slew of other products, that make you fat, and at best slow your body fat loss. Other companies, with a diet and/or products to sell have taken up the scam. It's for people who want to pretend to be on a diet to lose body fat. Goes well combined with a Planet Fitness membership, for getting in shape.
If you want to lose body fat, and keep it off, then don't eat carbs at all. Everything else is just a case of fuckingarounditis.