Let me be more clear then.
I/we cannot decide to take someone off life support in any circumstance. If such a question arises, it is the duty of the next-of-kin to get a psak from a competent Rov. End of story.
I was talking about the issue that the world is facing about limited supply/unlimited demand for healthcare. My point was (is) that there will come a point where rationing will be a forefront issue, instead of a behind the scenes one as it is now. When that happens, the individual may not be able to decide to have a hospital dedicate resources to his/her relative just because he/she wants it that way.
Hashem Yishmor.