I agree with your assessment that this was likely unintentional, although it doesn't seem like they forgot to change the URL, but rather that the whole component should have been disabled. https://news.ycombinator.com/item?id=19451772

On the off chance that you're a native Chinese speaker, are you able to figure out what the purpose of device self-registration is? My Chinese is unfortunately not good enough to easily find information on it.