True. It doesn't. But as far as I know, there is no deep technical reason why it can't. The dots in domain names are '\0', and a few characters ('@', in part

True. It doesn't. But as far as I know, there is no deep technical reason why it can't. The dots in domain names are '\0', and a few characters ('@', in particular) need to remain reserved, but other than that, what stops UTF-8 from being used?