while i may agree with your conclusions, i have 2 objections to your argument:
1) you claim that Rothbardians believe that
"As soon as the State withers away, the Utopia will be realized."
One sign of a weak argument is the need to miss-characterize the position of an opponent.
I challenge you to source a SINGLE quote from any Rothbardian who makes this claim (or anything even resembling it).
They do not claim that Anarcho-Capitalism will bring about "utopia" - only that it would be preferable to the alternatives.
2) "Anarchism. This is a pre-civilizational "anti-social system" where there are no organized state institutions..."
So there can be no "civilization" without a govt, and anarchists are "anti-social" ?
Good arguments need only logic and reason - not insults.