You have to understand that mental health is one issue and advance requests quite another. It's true there's no medical or societal consensus on mental health. We're told the psychiatrists are split 50-50.
That being said, there's a very broad consensus across Canada on advance requests associated with neurodegenerative diseases, the best known of which is Alzheimer's. Some 82% of Canadians are in favour of advance requests. As I mentioned, cognitive neurodegenerative diseases will put an enormous weight on the shoulders of patients, first, and their families, second. This is increasingly the case, and it's increasingly prevalent as people advance in age.
Advance requests enable individuals with an established diagnosis to say, while they're still capable of making a decision, that they want to receive medical assistance in dying once they've lost that capacity, in such and such a condition. It is the essence of the law in Quebec both to enable those individuals to retain their dignity and to help them live days, months or even a year or two longer surrounded by their families and loved ones, even if they've lost some of their capacity. That's the principle of advance requests: to honour people's dignity to the end of their lives.