Dear Nick,
you made a point there. ICANN is ONE of several roots. 99% (thats a guess) of all ISP's use the 13 ICANN root servers, the exception are those ISP's that are in dictatures like China. China runs their own rootzone for example.
If you are an average american, or average german or latvian, brasilian or whatever, and if you connect to the internet through an ISP, then you use automaticly ICANN's root.
So even if YOU would run ".dubai" at the INAIC zone, nobody could reach the "domains.dubai".
TLD's ARE complicated :yes:
And yes, the INAIC website looks stupid.......! You probably need some plugin for your browser to reach the TLD's they have added.
Imagine that the USA, Europe, China, India and so on each had their own RootZone. Within that RootZone everything would be OK, but if I sit here in europe, and want to go to DNF.com to write this message, then I am already lost, for maybe dnf.com in the EUROPEAN rootzone would route somewhere else than in the US rootzone.
It's vital that there is only ONE root. And everyone uses ICANN's root.