Nation states are more or less required until a post scarcity economy becomes realistic and then basically they devolve into more and more voting entities that do things everyone agrees are necessary but generally less and less interesting unless a person has a particularly strong interest in a topic. (like say building codes, traffic engineering, licensing, etc.)

Nations can’t just disappear, anarchy always transitions to tribalism to monarchy to ... etc.

It's certainly not an easy system to unwind. I often wonder why we accept living in an emergent system rather than a designed one though. Our systems now can only be described as a patch work with all the baggage of history attached (colonialism etc). Right now feels like a great time for a large refactor though unfortunately given our path dependency, the political in/out-fighting and stagnation, it makes this near impossible to implement.

It's easy to think you could scrap a mature system and design a simpler one from the top down (or do a sweeping refactor). Sometimes this is true, but often you're simply overlooking years of edge cases and bug fixes that allowed the system to become as robust as it is. Emergence in itself is not a bad thing. It means the system grew from the necessities of reality rather than someone's imagination.

I'm also not sure what the real-world realization of scrapping a mature political system looks like if not violent revolution.

Rewriting my entire home operating system to be the ideal may be a fool's quest, because one person will never be able to do as much work as the hundreds or thousands who developed the code he is replacing, but if you want to try it is entirely on you. I can putter away in my basement for years without bothering anyone.

Replacing or reforming a political system is fundamentally different because it requires the buy-in of a large portion - a super-majority ideally, but at least a powerful minority if you're willing to play violent or dirty - of the population to get started. And you can't just show up out of the blue with A Plan and expect people to all be on board - even if your plan is really quite good, human nature means almost no one will want to commit to someone else's plan. So you have to develop your plan in a group, making compromises that you may personally disagree with to get larger and larger groups of people on board, until, unless there really was a large number of dissatisfied people in your camp all along - which we all want to believe but is seldom the case - you end up politicking your way to a revolution that is barely different than the status quo.

There might have been a shot at this 30 years ago. "We have a real chance for a new world order" wasn't just empty talk. The US as the sole remaining superpower could have led the world under an increasingly potent UN. But it was sold poorly. People correctly identified it as dystopian, but failed to recognize that NOT doing it would almost certainly lead to something worse.

"I often wonder why we accept living in an emergent system rather than a designed one though."

Because we ourselves, our bodies, are an emergent system rather than a designed one?

Human biology seems to be even more chaotic than various political systems on Earth, but both have one great advantage under their belt: they survived unexpected crises in the past.

Designed machines tend to be nowhere near as robust.