I agree that everyone deserves the option. If an animal is sick, we put them out of their misery, no questions asked, because we believe that no living creature should suffer when there is a way to end that suffering... I've done it myself with my pets...
So why not extend it to humans? I've worked in the nursing business and tbh getting old + incurably sick terrifies me because people are literally left in agony and depression because there is nothing doctors can legally do to end their pain... It's very inhumane but sadly true...