@Goosefoot I've only just finished cancer treatment. I was treated at a specialist cancer hospital. I don't need you to explain to me what terminal illness can look like, or our relationship with mortality.
I disagree that euthanasia is worse than unalloyed end of life suffering. It can't always be overcome, and when death is inevitable, allowing people to die with more dignity and less suffering seems to be to have great value.
The key risk is abusive relatives or people in other way likely to benefit financially, which is why the courts should be involved, and the capacity of the person in question ensured. As to attitudes changing - I don't think there has ever been a time in history when people are so insulated against the reality of death. It's rarer in young people, we can extend life far longer, and most die in medical settings, if it's not a sudden death.
Allowing people the right to determine when life has become unbearable, when they are terminally ill, seems to respect both human dignity and bodily autonomy. It should be the right of the individual.