The studies you cite are statistically meaningless, especially since we’ve known from the 1920s that observer effects (Hawthorn effects) can produce temporary improvements in task performance regardless of the stimulus being applied. The studies cited in your article are merely an embarrassing example of how poorly so much science is still conducted: no control group, inadequate sample size, absurd conclusions from flimsy data.
Furthermore, as the brain is highly complex (100 billion neurons with up to 20,000 connections each) the idea that a simplistic approach can create intentional complex outcomes is, to put it mildly, wildly optimistic. The truth is that we are at the very beginning of understanding how the brain works. Perhaps, if our civilization persists for another 200 years, we'll reach the point where we not only have suitable technologies but also have sufficient knowledge to begin to tinker with the brain in a purposeful way. Until then, Musk and his imitators will remain masters only of hype, and sci-fi will remain a very poor guide to reality.