What you describe is exactly what is already implemented as an estate tax. It makes perfect sense to do so. Furthermore, an estate tax has the benefit of prev

What you describe is exactly what is already implemented as an estate tax. It makes perfect sense to do so. Furthermore, an estate tax has the benefit of preventing a class of aristocrats from forming, by limiting the amount of wealth that can be passed down through many generations. Default organ donation is different in two ways. One, you can opt out at no cost. Two, the organs would otherwise benefit nobody. In the case of an estate tax, the assets are split between the descendents and society, and nothing is lost. In the case of organ donation, the organs go either to recipients, or to the worms. Clearly, the default behavior should be the one that allows some benefit to be had.