They're not talking about multiplicity. They're talking about the different aspects of someone's personality and how they can be in conflict. This guy is just taking it a step further and theorizing that everyone makes committee decisions with themselves.

I don't get why multiples always jump on these things. It's like pointing to inner child work as an example of multiplicity. They're not the same things. Even when the psychologists and philosophers are talking about multiplicity, they always get it wrong and turn it back into everyone in the system really being part of a whole which reflects to people having many aspects of their personality.