I believe in Aus and UK it is banned "unless it is a working dog." Not sure about South Africa. It's legal in the US, but there is a push from some to get it banned.
My baby is docked. I love his little stump especially when he's excited and it wags furiously. I keep waiting for his butt to lift off the ground. lol There are a lot on here with babies are not docked and those tails are the cutest things.
It would be recommended for AKC confirmation standards, but it is by no means any sort of health recommendation.
Originally these little guys/gals were bread to go into tight spaces and hunt mice and rats. Docking the tails gave them protection from being bitten on their tail. Can't bite what's not there.
I believe the long coats were favored as a form of armor. That's how the modern yorkie came into being.