In various articles in the past I have made a monist objection to a dualistic concept of self-ownership due to the problems that an absolute mind/body dichotomy leads to. To summarize the problem: who exactly is it that is doing the owning? If I own it, then it is not me. If I am owned, than I am not the owner. One cannot be both the owned and the owner at the same time. Using the analogy that the mind owns the body doesn't really work because the mind is also part of the body. There is a coherant whole in reality, the mind and body are not metaphysically detached to the point where we can treat them as completely independant entities.
Hence, the way in which libertarians commonly put foreward the concept of self-ownership is flawed and must be revised to what is really meant by the concept, I.E. individual sovereignty, which is an ethical concept rather than a descriptive one. The problem is that when libertarians argue for self-ownership, they tend to treat it as if it was descriptive. So they will put foreward an argument along the lines of what Hans Hoppe's argumentation ethics and Stefan Molyneux's UPB would put foreward: that by virtue of you argueing and generally purposefully acting, you implicitly aknowledge self-ownership. But this is to totally confuse an is with an ought, or descriptive ethics and normative ethics.
It goes so far as to completely conflate categories of philosophy and definitions, as this reduces to an attempt to make a metaphysical argument for self-ownership. "Individual sovereignty" is really what is usually meant by the term self-ownership, but it is also often used as a sort of mix of different concepts like conciousness, free will and individual sovereignty. This is the sense in which I think the self-contradiction argument starts to fall apart, because conciousness or free will by themselves, while they are a necessary condition for personal sovereignty, are not the same thing as the ethical right of personal sovereignty. So the argument may apply to those who deny conciousness and free will, but it is ultimately erroneous to characterize arguements against self-ownership and property rights as necessarily being in denial of conciousness or free will. In this way, I think that self-ownership has a danger of being used as a package deal concept.
What's in dispute is not necessarily conciousness or free will, I.E. the capacity to have individual sovereignty as opposed to the substance of having individual sovereignty itself, what's in dispute is a specific ethical theory or principle. Therefore it does not make any sense to put foreward purely descriptive arguments as if they justify a particular ethical premise by themselves. Proving that someone has conciosness and free will is simply not a sufficient proof by itself for the ethical right of individual sovereignty, and neither is the mere fact that individual sovereignty is internally consistant as a concept (although half the problem here is that libertarians themselves aren't always internally consistant in their definition or use of the concept).