People can suffer with severe depression over many years despite trying multiple treatments, others mays want to end their own lives to avoid the most painful stage of a terminal illness. They want a fairly peaceful and painless way out, and don't want to leave a horror movie scene for somebody to clean up afterwards. They may consider their options over a fairly long period, and may research or even discuss methods online.
But Canada's experiment with this is showing the potential dangers of that, of offering euthanasia as a 'solution' to poverty in old age.
Nobody needed Canada for that. That option has always been on the table and plenty of people have taken advantage of that. It's not as if Canada was keeping disabled people out of poverty before euthanasia was an option. I don't think very many people are saying that Canada shouldn't improve conditions for people just because poor could simply die with government approval instead of dying illegally they way they always had been.
If you make information about effective and readily available ways to end ones life available, people harboring bad depression will read that, acquire these tools and use them on impulse during a dark episode. And we can discuss control over one's own life and body more, but if depression forces a person to take their life because today was worse than yesterday, are they in control of their own situation? Those people need help to sort their own being out, not help to choose death.
And that is very different from someone overall committing to end their existence on their terms, because there is no way for it to become better. Knew a guy in chronic pain who spent half a year socializing their pets with a few friends, gave away all their equipment in a sport, canceled all contracts, wrote down his last will, setup a call to emergency services two days after and then went to a long sleep.
If you don't make that information accessible, people harboring bad depression wanting to kill themselves on impulse during a dark episode will just jump in front of traffic or off the nearest bridge or try whatever pills they can get their hands on or any other means they can find in total ignorance.
It's not about helping people choose death, it's about making sure that people who have already made the choice have access to the information they need to get their affairs in order and can end their lives as peacefully and assuredly as possible.