My little 10c bit of wisdom, coming from someone that actually likes the Treatment a lot and wants to make this part of the game work and be comfortable for everyone (except for those who would kinkshame others for liking the bimbo fetish and a culture built around it - those can get lost, since this is a porn game after all):
a) Explicitly establish once and for all in game lore that the Treatment (and other stuff like Dumbfuck and Gush) does not turn anybody stupid or brain-damaged in a conventional sense. They rewire you brain to amp your libido and put libido-related tasks near the top of your priorities. You get features like Weak Will b/c you know, your instincts got amped up, and Weak Mind b/c your brain got adjusted to work with a different OS and deals with non-libido tasks in a different way. You can re-train it to work the usual way but it takes time and effort or you need the promise of a sexual reward or being in state of sexual satiety to work in an optimal way. It would help if there were other examples in the game of Treated characters besides the PC that remain competent at what they like doing besides sex - they just need a lot of sexual fulfillment to work optimally, but that's just a lifestyle need and one actually fairly easy to satisfy in this liberated society.
b) NT doesn't actually force anybody, including its coming-of-age citizens, to take the Treatment. It's just they built their entire society around it so there's a lot of peer and social pressure to take it. If you don't, you eventually get forced to leave, one way or another. They don't punish you or anything, it's just you really don't fit, so you feel pressured to take it or go into space. If you choose the latter, they send you away with a smile, all the way shaking their head and wondering about why you don't get it and opt out of their paradise.
c) Reaha got massively conflicted while coming of age about taking the plunge or not. She eventually chose to leave but her inner conflict was so bad she got a psychotic break and hallucinated what was a fairly typical case of legal immigration and a young person running away from home into a desperate flight to avoid being forced into the Treatment by her parents and the non-existent NT secret police. Her instable mental state and persistent inner conflict between fetishizing being a cowgirl and desperately fearing the effects of the Treatment drove her into all the stupid, self-destructive stuff we know.
d) Visiting NT and her parents causes her conflict to resurface and she breaks down again. In order to get better she has to face her fears for once and live with the consequences. She needs Steele's help and advice to appease her inner demons and stitch her psyche back together one way or another, either by rejecting the Treatment once and for all, or by willingly and knowingly accepting it.