It works, but very slowly
It works for me. I've been doing this for three years and my eyes have improved by about 0.75 of a diopter. That being said, it did take me 20 years to get to a -7.5 prescription so it could take another 20 years to go back. But it's better than my eyes getting worse every year as I was fearing that one day I might get to -10, which is really scary. It's all about commitment and implementation, I just wear my differentials as a habit now during near work. It's not a race, it's a journey.