Earlier quoted context omitted.
People with dependents are one case that comes to mind when considering why this might not be a great idea. Elderly people with no dependents are one example I can think of why this might not be the worst thing in the world. But in general I tend to agree that there should be some means to humanely end ones own life that doesn't automatically presume insanity. I think there's probably a reasonable middle ground to be…
Re: dependents, should you not be allowed to kill yourself if someone (let's say a selfish spouse rather than your infant child) depends on you? That might even be the reason you don't want to live anymore...
At least in the case of children I don't think one should be able to since the cost of caring for them is transferred to society. It's also pretty shitty for the children to lose their parent. Is the death of a parent worse for the children than witnessing that parent be in a perpetual state of misery? Harder to say.