We recently put forward an argument, the Unfolding Argument (UA), that integrated information theory (IIT) and other causal structure theories are either already falsified or unfalsifiable, which provoked significant criticism. It seems that we and the critics agree that the main question in this debate is whether pure first-person experience, independent of third-person measurements, is a sufficient foundation for theories of consciousness. Here, we show, first, that the use of pure first-person experience relies on non-scientific, neo-Cartesian reasoning. Second, even if this reasoning is accepted, it leads to consciousness being entirely epiphenomenal, with absolutely no causal power. Third, consciousness would be fully detached from the content of reports about subjective experience. A human may report to perceive X but their content of consciousness is Y. Hence, IIT and other causal structure theories end up in a form of dissociative epiphenomenalism, invalidating pure first-person experience as a viable foundation.