I think it depends. If the person has found another way besides meds to manage their illness, that's great. But I do have a problem when someone constantly complains about their symptoms and allows their mental health to negatively affect others but refuses to consider getting treatment. It's not just with mental illness. I once had a room mate who didn't believe in western medicine yet would wake me up crying in pain every night because her stomach hurt. She finally went to the hospital and lo and behold, she had a burst appendix and less than 24 hours to live without surgery. Needless to say, she now believes in western medicine. MI MAY not have such devastating consequences, but it could.

That being said there's plenty of other reasons people are unmediated besides willful noncompliance. So I don't make that assumption when I see it here.