From the post: "I want to live [...]"

I am saying this completely honestly, with no sarcasm:

I truly hope that you never have to experience (or witness a loved one experience) the kinds of illnesses/injuries/diseases that would make someone consider assisted death. It is a blessing that you can't imagine the situation. Because the situations that make you consider assisted death are awful.

The heart transplant will have them live in a state of uncertainty, most likely having to use a defibrillator until a suitable heart is found, if it is found. It is risky, with many points of failure. As such, a certain death of their own terms might be more valuable than a chance of a life with the certainty that they will have to go through the suffering that has already driven them to disable the defibrillator mixed in with some more risk and pain. It would be a rollercoaster ride for the hungover, except they don’t know id they will get to step off. And the loved ones get to watch on from the side lines. Even with all that, it is tough to imagine not opting for the transplant, but this should just serve to help you empathise with pain they are going through.

I think the same as you, but I recognize that those in such circumstances now are literally experiencing horrors beyond my comprehension. However bad you think it might be, it would have to be unspeakably worse, which for some, it evidently is.

Can I ask you how old you are? Because at my age (50s), I've pretty much experienced what life has to offer and made peace with my mortality. I'm in no hurry to die, but I could die any time and not feel shortchanged.

Nobody knows what would they do in extreme circumstances until they end up in those circumstances.