As a brief aside, it's worth contrasting the libertarian "consent principle" with the Kantian principle that one always treat others as ends in themselves (and never as a means only). These are often confused - especially by libertarians who want to make their position sound less awful. G.A. Cohen offers some helpful clarifications:
The difference between them is the condition satisfaction of which does allow you to use another person as a means: for Kant, using someone is all right provided that you treat the person you use as (also) an end, while, for Nozick, it is all right provided that you have his consent. To see the difference between these provisos notice that a capitalist employer may scrupulously observe Nozick's consent requirement while not caring two hoots about the welfare (or anything else relating to their status as ends) of his employees, and that the state which taxes the able-bodied violates Nozick's consent requirement but may nevertheless respect their humanity. (Self-Ownership, Freedom, and Equality, p.241)
Now, one way to argue against the libertarian defence of capitalism is to grant them the self-ownership thesis, but deny the assumed right to acquire external resources. We might instead say that only provisional/custodial rights will meet the requirements of justice in preserving natural resources for future generations. Or we might hold that natural resources are initially owned by everyone rather than no-one. On this view, a self-owning individual may not make use of the common resources without others' consent. (And perhaps the price of that consent will be that the products of his labour must be shared between them all.)
This demonstrates that self-ownership is a merely 'formal' notion that does not guarantee any substantive freedom or power over one's own life. As Kymlicka asks, "how can I be said to own myself if I may do nothing without the permission of others?" (p.122) But the poor and disadvantaged face the same problem within a capitalist system, and right-wingers are unconcerned by their lack of substantive freedom. Thus they have no grounds on which to complain against this egalitarian dystopia, for it violates no rights that capitalism doesn't.
But we should reject both systems, if what we really value is substantive self-determination. Our aim should be to enable as many people as possible to live the lives they want to live. We should ensure access to education, healthcare, and basic human needs like food and shelter, since all of these are essential prerequisites to any form of freedom worth having. If provision of these requires us to compromise self-ownership, so be it. The latter has no value in the absence of the former in any case. (Besides, self-ownership has the absurd consequence of condoning parental neglect.)