>>9818984human organs aren't modular because of how our immune system and recovery systems work
it's why organ transplants not only have to be racially selected (and preferably related) but they have to take immune system depressants from then on to prevent the body from identifying the new organ as a foreign cell that must be destroyed. that's why they don't last long after: your immune system is constantly working to fight off things that normally wouldn't be a problem but if it was weakened they could cause super nasty infections
your immune system has to check your organ cells in addition to just invasive cells because that's how your body makes sure you don't develop cancer at 30
