Gov.uk is basically a pre-LLM america.gov that was done beautifully well. And you're guaranteed to not get hallucinated answers too. Searching and indexing works on it beautifully, as do the many functions you can carry out from the web itself instead of visiting a govt office in person.

Everything Americans do has to be very patriotic with giant flags and shouting AMERICA. So no you can't just have gov.us

It's rijksoverheid.nl in my country- good luck to any poor expat trying to pronounce that lol.

canada.ca is the Canadian government's equivalent, as far as a web 1.0-style portal/index into many other sites and resources.

Neither the UK or CA versions have "here's an LLM you can make general inquiries to" though; at least for now that appears to be unique to america.gov. Unclear to me why this required a separate domain with all this branding on it vs just being one of those "let our chatbot help you out!!!" popup widgets on the existing usa.gov.