That the chair persists is proof enough that it's a valid treatment device. That Adams abused it is neither here nor there - Noel is familiar with the technique even if not with the equipment, and comfortable with it, supposedly because Adams for the past 20 years has been utilizing it for good.
The new drugs helped out a patient who was previously declared uncurable by the UFP crime management institution. Supposedly Garth would already have been in the chair, then, having spent time in a place akin to Tantalus V before being sent to the one and only Elba II.
Prior to "Dagger", archaic crime management methods such as jails may be in use, even in the civilian world and outside the extreme wartime situation described in DSC a decade earlier (Burnham's cellmates certainly weren't Starfleet, and we didn't exactly learn they would only have been imprisoned within the past few war months). A prison satellite has already been abandoned for some reason in the second season of that show. After "Dagger", supposedly jails would go out of fashion altogether, and quickly at that - literally only a handful of people are kept behind forcefields for their incurable criminal insanity.
Does this get reversed at some point? Is the prison sentence of Richard Bashir a rare case of an enraged judge throwing a dusty, centuries-old book at a man who broke mankind's greatest taboo - or a sign that Adams' ideas have been discarded and freedom deprivation torture again is the way to go? In contrast, Garak gets a "sentence" of a couple of months for attempted genocide, in line with him receiving therapy (perhaps those same drugs that cured Garth of his desire to attempt genocide) but not with him being subjected to freedom deprivation commeasurate with the severity of his crime.
Hard to tell. Tom Paris is confined, but for therapy or for deprivation torture? The length of his "sentence" (quotes again to signify it was not called that) can be adjusted with Janeway's interference, but what does that tell us exactly?
Timo Saloniemi