I don't know which trailer you watched, the one I looked at has him saying he is depressed and is only like 30 seconds long; he doesn't mention success in life. I can't remember the specifics, but I think he had been in therapy since he was a toddler so he'd been through all the healthcare/lifestyle interventions which is why he was allowed to euthanasia in the end.
On the outside, he's actually more successful than many here because he participated in the supportive state and community. He participated in the hobbies, classes, volunteering, had friends, hobbies, and as such evidenced he found life unbearable despite the claims of what fixes the mind.
You are inserting a lot of aggressive assumptions, possibly because you are envious of his position in a western welfare state and his low social value being fat? No he isn't some magical ideal but he's still one of the few examples of someone peacefully facing euthanasia because he doesn't find value in living on film. And with a family that understands after seeing decades of struggle.
It doesn't matter, imageboards aren't the place of meaningful conversation.