@sneakypete The stylist who does my unruly mop of hair received a new kidney back in November and is still not fully recovered. Only works part time now. She might be back to full time before the end of the year., but it's been a long haul. So I know from what she has told me how hard it is. My own kidneys were in bad shape some years ago and it was thought I might need dialysis and put on the transplant list. But then a sharp specialist did some research and determined that a blood pressure medication that was supposed to be good for my kidneys actually was harming them. So I went off the medication, went on a low protein diet for people with kidney disease, and now I improved so much, dialysis and transplant are no longer mentioned.
You're right that having the disease is bad and without treatment, eventually, it's fatal. Dialysis helps to some degree, but it only postpones the inevitable at least for a time. A transplant , if successful, improves one's longevity, but many transplants fail. Often it is difficult to find a compatible living donor and a patient on the transplant list can wait years for a cadaver kidney. Many patients die before their number on the list is up. It's a terrible disease that can't really be cured; a pill or potion won't do it.
And about your classmate from gunsmith school: Perhaps having been so close to dying and being saved by his transplant made him think about his life and realize that he needed to make some changes, particularly in his attitude. Maybe it dawned on him that life isn't so bad after all -- considering the alternative.