I came across this article, which was published in a general interest magazine, written by a noted researcher in Medical Ethics who is also a long time practicing oncologist. The title given to the article was the publication's and the author made pains in an interview to say it is somewhat misleading as to his intent.
This well-known doctor and professor is not close to the age of 75 which he has decided is the age at which he will not take any extraordinary measures to extend his life. He will get medical care for things like fractures and pain but will not get heart surgery or chemo or .....
He is not suggesting in any form or fashion that anyone else should follow his philosophy about QoL and therapy. He just describes how and why he came to the decisions he has. I found the article to be germane to PCa as a potentially terminal disease, for which QoL is an essential factor in how they make treatment decisions.
Projecting who we will be and what decisions we will make in a hypothetical future is a fool's errand. I have sat with (too) many on their deathbed who wanted some extra time. Also, you are posting on an advanced PCa forum. Many don't get the choice beween QOL and length of life for the reason that the same drugs that increase one also increase the other (e.g., chemo, radiopharmaceuticals, hormonal therapies). I think few would want the pain, crippling and suffering of living with metastases, even for a short time.