Here is 1 scenario already being done at Endeavor Air. Management will pull aircraft out of service parallel with attrition. Eventually the airline will:

A) liquidate. In which flying would be returned to mainline if the "shortage" continues. The majors in the future will try to create regionals again when the day comes again when they are all going bankrupt.

B) get flow to attract pilots to work for these wages.

C) get better pay to attract pilots.