Incalculable because there's no way to know how much time a terminal patient has left. Art Buchwald was pronounced terminal with kidney failure, with a life-expectancy of weeks, checked himself into a hospice, planned his funeral and made his farewells to friends and family, waited and waited, checked himself out after a couple of months, and wrote another book ("Too Soon to Say Goodbye.")
You never know.
It's inapplicable because every life is incommensurable. It all depends on what human life is for.
If you think most other people's life are for "nothing," you could persuade everybody over 65 to kill themselves and and save a whole sh!tload of money on future Social Security costs: but why? What for? And what does that make you?
That's it, in a nutshell. But some people just don't get it. They know the cost of everything, but the value of nothing.