This reminds me of the show House MD where Dr. House would say that patients lie all the time... and apparently true. Thankfully clinicians are trained to see those lies lol.
I think that the pill's purpose is to make them happy is quite a common misconception and I've heard that a lot. They seem to think it didn't work or it's giving them "negative side effects" is because they didn't see life in colors like they expected. I've heard the "robot" and "kills creativity" effect a lot of times and honestly one of the reasons why I delayed going to a psychiatrist for help. It is indeed a lot better to feel neutral than being on the negative side.
Pills can't solve everything.
I used to be suspicious but when I got in the training, I became more trusting and it backfires a lot and it's charged to experience. For artists that make money out of their depressive state, the pills may actually affect their creativity because now they are stuck with feeling nothing and it reflects on their art and their art is noticed by their patrons that want to see those depressive themes. This is the part where people need to decide whether they actually enjoy being depressed or want that neutral state. I think being in a neutral state is zen mode and when people are so used to having turbulent lives and thoughts, it may be an unpleasant experience.