Comment by WJW
It's not just those two choices though. It could be "6 months in relative comfort" and "10 days begging each minute to die but you can't because you're borderline unconscious". Or anything in between. Just saying.
Medical guidelines are there for a reason and are often, as they say in the military, "written in blood".
Having seen the last ten days of pancreatic cancer, there isn’t really a difference with what you’re describing.