Transitioning a Society towards Anarcho-Capitalism is wrong.
Society ought to be transitioned towards Freed Markets. From within the scope of Freed Markets people may choose how they wish to organize themselves (this is where Anarcho-Capitalism, Communism, Syndicalism, Primitivism, Mutualism, Left Libertarianism, Right Libertarianism etc come in).
Why? Because many people will reject Anarcho-Capitalism and as such it will have to be enforced, through a State, the same problem Lenin and the Bolsheviks ran into. And once you start doing that... you make enemies and you need to protect a central hub (State) so it hires security (Soldiers/Law Enforcement) and then you're right back where you started.
You make a good point, that it's actually free markets we want, not a
specific method of organizing those markets. But in my opinion, AnCap is the best way to ensure those free markets, because the services which define it are provided on those markets, and it is permissive of other systems within it's framework. "Enforcing AnCap" would amount to enforcing a free market, Which AnCap does quite well on it's own, without a State. Remember that market systems are not mandatory, nobody forces you to sign up with a defense agency, or any other AnCap construct. You're more than welcome to join a commune or arrange yourselves in any voluntary way you choose.