Healthcare in the US is run for profit. From 2020 estimates, they charge $1.6 million for a heart transplant. $1.3 million to transplant a pair of lungs, $880 thousand for a liver, and $440 thousand for a kidney. This is what for profit hospitals charge patients while giving your next of kin nothing for the organs that made it possible.
They don't pay you for your organs. They will still bill your estate for any care other than the organ removal despite your generosity.
I would happily be an organ donor in a country with a non-profit healthcare system. But because of how heathcare is run in this country, I would rather my organs be left to rot.
I agree it's horrible, but also I don't see it as a large enough reason to not donate. The person receiving the organs is probably not the cause of this. It's like not working because your labor mostly goes to the elites. It's not a great plan, even if it does feel good.