I think the vast majority of mental illnesses are fake
What makes you think that most mental illnesses are fake?
They are fabricated by the individuals to convince others that they are sick, instead people who are left unmanaged at critical time in life are making up psychiatric issues.
It can be hard to understand an illness when you are not suffering from it, but you should believe people when they tell you they are suffering. People will think you are judgmental for judging others on their mental illness.
I'm not judging them, I just want to take them from their lies and expose them for the weak individuals that they are.
Your attempt to "expose" others for supposedly faking mental illness has the underlying feeling of thinking that other people are bad because you think they are lying. Take a look again at what you think is and isn't judgment.