The Role of RPOs in Fantasy Football

RPOs more or less take away the reading of a set of routes in favor of a design receiver who will get the target only if the play is a pass because it will otherwise just be a handoff. Team wide receivers with mobile quarterbacks absolutely see lower fantasy point totals objectively. But then why does that not seem to show up when comparing to ADP expectation? Why are those players not overvalued by the market each season? And I think RPOs may have something to do with it.