The solution to this is simple. Instead of calling it "pay based on what you can hold", call what it is. "No pay differential for equipment". Pay is based on seat and longevity and nothing more. The company actually loves this because guys stop chasing airplanes with a higher pay rate (reducing long course training) and pigeon hole themselves where they want to be. Of course other airlines go crazy because you end up with some pilots who are junior flying wide bodies at their lower hourly rate and that's viewed as "lowering the bar".

This is what happened at AWA. If you had to tell guys you flew a 757 to Hawaii, that's what you did. It you were a QOL guy, you flew the 737 up and down the West coast. Everybody else fit in the middle flying the Airbus...and it drove other airline pilots nuts.