With all due respect, I think you are missing Dr. Joel’s point. It’s not mean to juxtapose the specifics of the drug treatment for diabetes and mental illness (per your insulin is missing explanation). I think Joel is simply saying that people with diabetes and mental illness often both need drugs, and that thinking to cure them all or even most of the time otherwise is unreasonable and unrealistic. You have offered a strawman argument and seem to be mischaracterizing or misunderstanding his point. Cheers.