Fetterman always looked like a guy who scarfs fast food burgers for breakfast, lunch and dinner, and doesn't have the slightest idea how to take care of himself, hygiene-wise. He might also have been a heavy boozer or drugger on the outside. He's been in a place where they serve you healthy food, and make sure you're clean, well-rested, and properly exercised, and where booze and drugs are verboten. That can make a massive difference. I have experience with a family member who went in and out of long-term rehab, where the facility and staff did the things I just mentioned. He did look radically-different coming out than he did going in.
Let's not be so quick to say it's the AI Fetterman (he doesn't have much "I" to begin with, anyway). Hospitals like the one Fetterman has been in do incredible work. I saw it with my brother.
In those hospitals they don’t change the shape of the patient’s head nor do they give him a crooked nose or round the pointed head. look at the two pictures side by side. If it were a deep fake they would have got it better.