No route authority belongs to any pilot, but flying (including routes) very much can belong to a pilot group WRT that flying or route being done by a particular company.

Seat limits, gross weight limits, revenue and code arrangements, distance and yes, even city pairs, very much DO belong to any pilot group that bargains for them WRT that flying for a particular company, including holding company.

DL (pilots) haven't bargained for SUX-MSP specifically, but they easily could and if they did, no one else could fly that route...for DL. DL does have some specific city pairs covered in their scope as well as distance limitations as a percentage of over all lift in the PWA, and could further bargain complete ownership of city pairs if they so chose. SWA could still fly it, UCAL could still fly it, SkyBus II could still fly it, etc. But no one else could fly it for DL. Just like certain sizes of airplanes.

Pilot groups with scope own the flying covered by that scope WRT their company. You're trying to imply we're all just a bunch of helpless victims with no say in our careers and you are very wrong on that.