Why decrease route structure when you can just decrease frequency, more than likely increase seat availability and first class options potentially increasing revenue. All can be done by putting a mainline aircraft on RJ routes. Pull 2 50 sweaters off the same city pair, fill in with an airbus or 737. You just cut pilot requirements in half, potential increase in revenue to make up the labor costs, helped alleviate the pilot shortage and even the RJ pilots don't lose because they need to get hired at mainline to fill those seats.

And the beautiful thing? It's already happening and will continue to happen. Delta started this a few years ago flying DC9s, MDs and Airbus on short flight such as ATL-TYS or to VPS or CAE.
United is doing the same and just announced between 10-20 used Airbus that will be used to replace 50 sweaters that are going away at an accelerated rate.

All that remains is for us at mainline to hold strong on scope (delta you're next) and it benefits all current and future pilots.

Age 68 gets tossed around but at worst it just pushes this *crisis* back 3 years. Doesn't fix anything.