Higher wages at the regionals mean it would no longer be financially viable for the mainline to outsource flying. The mainline would expand and create new, better jobs with narrowbody aircraft while the regionals would shrink...but that shouldn't cause any loss of jobs due to attrition at the shrinking regionals from their pilots taking jobs at the growing mainline.

Isn't that what we all want - more mainline jobs? Growing regionals don't make mainline jobs...