Subdivided geographic TLDs are still common in Ontario govts, such as gov.on.ca [1] and tdsb.on.ca for Toronto schools.[2] Both are still in common use.
Australia does the same for organizations regulated at the state level, like schools. However, while all other states/territories do $SCHOOL.$STATE.edu.au:
For Queensland it looks like private schools get a .qld.edu.au domain and state schools get an .eq.edu.au one. For example: https://www.twgs.qld.edu.au/ .
When I was at university, we had http://cs.mu.oz.au (Computer Science, at University of Melbourne). That domain name has stuck in my head, even though it isn't in use anymore.
country wide like that must be a bit of a pain for local web admins for those municipalities to make changes through the bureaucracy of government DNS/registrar keyholders. I have a friend who works for a university web services and adding any subdomain takes months to a year+ with committees, boards, meetings and approvals they have to go through first
There are still rules on who gets priority on names: toronto.ca is the government but toronto.com is a news organization; ditto for canada.ca and canada.com; ontario.ca versus ontario.com; etc.
The three/four-level domains are now generally grandfathered.
in what I find to be unfortunate, I have noticed a trend in the reverse direction.
http://shoreviewmn.gov/ should have a dot between the city and the state. they chose some form of human usability over precision. I trust it ever so slightly less, because it is cute before hierarchical.
https://www.mvpschools.org/ formerly https://www.moundsviewschools.org are the domain names for a school district. The fact they chose the P between mv and school (which stands for public) makes it look like phishing or social engineering. It erodes trust in both technical decisions and branding decisions made.
Because domains are hard to read, and people were never taught to read them, we lost out on being able to establish trust because something reads "mv.k12.mn.us" (or preferably us.mn.k12.mv) which is two characters SHORTER than mvpschools.org!
My old school district moved from a localized URL of this kind to a .org a number of years ago (in the early 2010s). It seems to just have become the style, but I never really got it. I'm sure there was a significant cost to migrating what was a perfectly working setup to a whole new domain for website and email!
[1] https://kagi.com/search?q=site%3Agov.on.ca&r=ca&sh=lUDz_I8Uq...
[2] https://kagi.com/search?q=site%3ATDSB.on.ca&r=ca&sh=jysEnEgZ...