Blame the people for when animals get too familiar with humans. Being too familiar makes it often too dangerous, because the animal still has its instincts.
The exceptions I would make is for anything that can be domesticated enough in skilled hands to live in the house of its owner.
My experience with the baby robin was that its natural instincts kicked in after I raised it in the dining room in a cage I made from netting and hula hoops and a hanger from the chandelier. It learned to fly thru the room and I cleaned up little memories for years. Once it was flying, I released it in the back yard and called it back for food. My neighbor ate out for years on the story of being awakened in the morning by cries of “Trilby!” Eventually it stopped coming for food, but I kept bird feeders going in case it needed backup. I tried to imagine what its mother would have fed it, but decided worms were not on the menu, so I fed it ground hamburger mixed with raspberries on a toothpick into its mouth. It seemed to get its liquid from the raspberries.
If it had chosen to stay, I would have kept it, but I relied on it making the decision. Obviously, I was a total amateur but I tried to think the issue out carefully. This was years before there were such things as YouTube videos.
People can adapt to animals as well as expecting them to do the adapting. There was this fascinating lady running a junk shop on Rt 7 near Danbury who sat in a rocking chair in this massive fur coat. She’d gotten it because she’d raised 3 baby squirrels and their claws were impressive.