I don't know if you'd self-identify as "neurotypical," or if you've had experience with people who do not, or if you have had experience with the drugs that are prescribed for those with pronounced mental disorders, but surely you can't think it's that simple. The distractions aren't the problem, although they certainly help to maintain it. Imagine profound psychic pain—which can branch through to emotional and/or psychosomatic pain—that engulfs you as a result of the fact that, for some reason, your brain is practically allergic to the standard way of thinking that most of all society demands. Neuroplasticity is probably a thing that exceptional cases exhibit, but I'm tremendously suspicious that your spartan regimen wouldn't just compound the problems that people already have.
Oh, I guess I should mention that I'm not sure if you're referring strictly to people who recreationally use stuff like Adderall or if you're referring to all people who use it. In any case, it would help to be clear in that regard. Though your advice is probably fine for those people who've simply succumbed to years of bad habits (guilty), I hope you don't expect it to be a cure-all for those who actually deal with the effects of strongly pronounced ADHD because I can assure you it's really not as simple as that.