Are you saying no-one would defend themselves? Or their friends? Or hire a security agency to protect their property? Or their neighborhoods? I'd say you're wrong.
No. What I'm saying is that those who want to be left alone will not outnumber those who want to rule others, in some form or another. Thugs will build themselves into warlords, and then as soon as they've got enough people, they will come after you. Unfortunately, being that us "leave us the ^&#$ alone" types are so few, we will easily be outnumbered, and even if we aren't outnumbered, getting "leave us alone" types to organize into an effective resistance without a government-like system would be like herding cats.
So, again, it comes down to getting the vast majority of the populace to believe in the NAP, which is not likely.
No, it requires that people take responsibility for their own safety and security, and if not capable of defending themselves they either purchase protection or have a lot of friends.
Which again requires a lot of people to believe in the same things, things that the majority of people currently do not believe in.
Yes, many of the arrangements that would arise would look and act a lot like governments do. But the difference is that it would be truly voluntary. My friends and I buy some land, build a neighborhood, and make the rules in that "city," and no outside agency is going to tell us what the rules must or may not include, and we can't claim to make the rules for property we don't own.
So you admit that it doesn't involve some sort of utopian thinking."Government-like structures" probably. But on a purely voluntary basis.
Purely voluntary governments are still governments.