There aren't any emoji TLDs - check https://data.iana.org/TLD/tlds-alpha-by-domain.txt for the canonical list.

There's nothing technically stopping an emoji TLD - after all, .香港 exists.

Not true, the new gTLD program allows Internationalised Domain Names (IDNs), e.g. the Japanese .みんな (minna, "everyone"). The ASCII label is not the same as the TLD itself.

I understand the TLD is not the label, but since punycode encoded TLDs use '-', aren't they excluded by the a-z rule?

I was thinking the same thing, and concluded that perhaps the label is not the actual ASCII domain name. So perhaps みんな's label is "minna".

or 💩.com

there was only one (maybe two) TLDs that would allow emoji domains names.. that was the famous .la TLD

and so you saw http://💩.la

that was my inspiration for http://shizz.it shizz.it allows people to create http://👿.shizz.it or any other emoji character mix, as a subdomain, which is then redirected to any other URL. Thus link forwarding.

By making use of emoji in subdomains, you can get around the restriction of no emoji in domains or TLDs.

;)