As I said, the negative selection is also a real thing. This said, a retail trader might not notice it amongst other noise in his book, but if you do anything remotely systematic it will add up. The real question is which cost is greater, commissions or suboptimal execution.PFOF is the real deal. Retail order flow has a great value. As long a the retail trader is getting the right price at the right time, and the broker (RH in this case) is getting paid for the PFOF, then everybody win.