In a whole lot of cases dying is, whether we like it or not "I/we/We[0] don't want to pay for it anymore". I have the experience of pulling the plug on my dad, not for financial reasons, but because it was very clear that he was going to die anyways and it wasn't worth the emotional energy to keep him around (luckily for us, everyone important had time to say their goodbyes and several annoying people had said their goodbyes too [1]). But it also brought into focus to me that we COULD have spent/forced the system to spend millions of dollars in extraordinary resources to keep him alive.
Medical technology is quite advanced these days. Advanced != free. And there's a thing where the longer you try to prolong someone's life the more progressively expensive it becomes, not just from a "price of care" perspective but an "[externalized] cost of care" perspective. Is it worth X carbon dioxide emissions to keep a person on a "level-III dialysis machine"? Is it worth X acres of rainforest to extract an anticancer drug to keep someone's cancer at bay?
Anyways the political divide, in the US, between the left's clueless utopianism and the right's underhanded support of market-distorting profitmongers, has become so farcical that it's impossible to question if humans should have "a general right to have their life extended" even if there are actual, difficult questions to go around.
[0] capital We, as in "the state"
[1] if you ever have the experience of being by the bedside of someone who is dying (n=2 for me), you will see people who come to visit, and have so much pathos, I suspect largely due to their own hangups about death. To be at your best in your role, you will want to shoo them away as quickly as possible.