Suggesting that people with mental health conditions do not self medicate with supplements that can be particularly harmful to those with mental health conditions is entirely reasonable.
Sure, this is definitely a strawman you could make.
Here in reality I suggested that those struggling with MH conditions shouldn't self medicate.
Melatonin should never be taken... is different from recommending not to self medicate.
The previous comment can also be read as "disregard medical advice if tells you to take melatonin"