My Pancreas (from transplant) is 16 years old as of yesterday and has never missed a beat, it's reaction to glucose levels has slowed over the years but that just means not eating a bowel of sugar in one go!! My levels have remained 4-9 all these years, the only time levels rise is when under general anaesthetic as the transplanted organ appears to "fall asleep"!! As for immunosuppressants I could counter with the fact that, for 5 years post transplant, I worked as a Caretaker in a Primary School and I'm guessing that you can imagine the amount of disgusting detritus that I had to clean up yet I never caught a single bug, even when the vast majority of those around me were dropping like flies.
So, IMHO, it's not all cut and dried, procedures are getting better every day and drugs are improving, I believe that a Pancreatic TP can now be carried out from admission to discharge in around 4 days, less for a kidney.
I guess "not for ever" is a fair statement but, when all is said and done, what is?