I do like the positive representation of mental health medication but it does kinda piss me off how inaccurate HJ's experience with SSRIs is. I know that because of how common SSRIs are Ally or Brennan has probably had firsthand experience with them or at least had someone close to them take some, so I know the inaccuracies are probably more creative liberties than due to a lack of understanding. And some aspects I feel are inaccurate may be true to their experiences
But SSRIs are not fast-acting. It takes weeks of reliably taking them for it to start to have an effect on your mood. You will NOT feel it right away. Most likely, you will feel worse before you feel better. And if you have been taking them, stopping cold turkey will also make you feel worse, both mentally and physically.
This is more of a subjective thing, but I also feel like HJ's personality switch would come more from SSRIs and therapy than SSRIs alone. SSRIs alone could definitely make him less angry and in that way nicer, but after hundreds of years of toxic masculinity being ingrained in him, he isn't going to snap out of it just because he's emotionally doing better