The organ board base their decision on likelihood that the receiver will benefit from the transplant (for a long time), so some habits that are medically relevant are taken into account: smoking, drinking, taking drugs, and when AIDS was a concern, having sex with people who might transmit it. All those also come a moral judgement so many people assumed that the board was making a moral judgement. They are not: having other conditions complicating the process is relevant; being old too. Being a crimimal is morally relevant but doesn’t come into the judgement of the board.

For lack of a better word, they are maximising the duration of the organ.

Yes, most of the time that’s true, and just about everything you mentioned can be boiled down to a single number.

Genuine ties do happen though, and at the end of the day the board is human.