That's not my reaction. He looks like a public policy professor to me. Again, these are related fields that often study the same things, but they approach them differently.

Economics is about decision making under conditions of scarcity. We study it through causal inference, which can be done with econometric methods that address the endogeneity present in economic data or through economic experiments or through theoretical deduction.

Public policy approaches are generally more descriptive than causal and more macro than micro.

To be clear, I have no problem with people studying things in this way. Different approaches have different merits and different shortcomings. Undisciplined is a reference to the value I attach to looking outside your field and being open to other methods.