Recently I've seen some articles that they've figured out at least partly how the immune system learns to ignore antigens. And have made progress with inverse vaccines.
Cross fingers perhaps that'll make transplants work without having to bludgeon peoples immune system to keep them from rejecting.
We don't understand the immune system enough to make transplants less risky.
We don't seem to know if QoL is better between those who take the procedure vs those who don't.
The ongoing costs to supporting these operations are crazy and the dysfunctional US system doesn't help.