Yeah, I remember "Charlie", but the book (actually short story) rather than the movie. I thought it went past "kind of" horrifying. Of course, people with Alzheimers (and some other forms of dementia) undergo this precise same transition, so it is not exactly unknown in our society.
And it STILL goes past "kind of horrifying".
“Flowers for Algernon” was the title of the book. Algernon was the rodent on which the drug was first tested, and against which Charlie was measured when he started getting the drug. Algernon died, and it was a consequence of the drug. Then Charlie realized he, too, would die.
The book was titled: Flowers for Algernon and it might be best described as a novella. Flowers was targeted at the young adult market, although I do not think that a genre by that name existed at the time. As a pre-adolescent reader in 1968 or so I found it quite poignant. Anyway, as I recall Flowers touched on the seminal moral dilemma fleshed out in the posted article. For the central character Charlie, the medical cure for his mental handicap brought on as many difficulties as it did benefits. When the effects of the treatment ultimately wore off and he returned to his original condition there was a sense of great loss, almost tragedy, but the reader was left with the sense that Charlie was happier with the mind of an innocent child, gaining comfort from his relationship with a pet mouse (I recall it as a mouse anyway, named Algernon) than in his exulted state as a troubled genius.
As a libertarian, I believe that every individual has the right to pursue the full flowering of his God given talents. It is a moral wrong to deny another sovereign being the opportunity to express themselves to the fullest, and the fact that others may learn important lessons of charity from them were they to remain in their artificially limited and helpless condition is of no moral significance whatsoever.
Having said this, however, as Flowers demonstrates, gaining knowledge is not an unalloyed good. Just ask Adam and Eve. It may well be true that some individuals suffering from Down's will be less happy when cured than they were suffering the chromosonal abnormality. Caregivers may not like some of the changes that occur to their personalities. But no one has the right to make this decision for them if they are capable of doing so themselves. And, if it is concluded that the individual does not have the capacity to make an informed decision about the procedure, society should presume that he would want it if he were able to make it unless it may be demonstrated that the procedure would cause bodily harm.