I get being skeptical when someone is SELLING a thing because people are terrible and take advantage of others. However, isn’t it possible for those who suffer from stuttering and speech issues that exposure therapy has merit? I was someone who was always a fast talker, I would slur my words, some words or sounds I could just not say and I’d wind up stuttering due to panic. Working a job where I’m on the phone 24/7 helped me tons. I was someone who didn’t want to ever call orders in over the phone or use drive through because I’d have to repeat myself. So I’d have to do it face to face so I could point if I got jammed up. So, even if there is a physiological reason someone stutters, there is likely also a psychological component on top of it. There is no one size fits all solution for everyone.