Everytime I see someone mentioning no nations, fictitious as it is, it reminds me of https://acecombat.fandom.com/wiki/A_World_With_No_Boundaries which was branded as a terrorist group in the game. Don't think national boundaries will ever be erased without economic incentive and hardship in the process. How would you refer to each land?
As far as I can see there is always going to be boundaries be it cultural, tribal or artificial. Tendency is just there. Look at SF for instance where there was one neighborhood that rebranded itself (The East cut).
Nation-states are a fairly recent invention historically speaking, and their benefits are somewhat questionable - it's entirely possible that they simply don't provide more benefits than the price of administration.
Humans lived in city-states for most of our history, I see no reason why we shouldn't expect the city-state to be resurgent in the current century.
As far as I can see there is always going to be boundaries be it cultural, tribal or artificial. Tendency is just there. Look at SF for instance where there was one neighborhood that rebranded itself (The East cut).