> Ironic, considering the opposite is true for planes. Although I do believe only one is typically in control/“pilot” at any given time.

In US civilian flying, one is the pilot flying and the other is the pilot non-flying (usually operates radios, etc.) They usually alternate landings. Pilots study Cockpit Resource Management (CRM) to improve communications.

The Pilot in Command (PIC) is responsible for the flight (not ATC.)

Airplanes can be towed on the ground. Not sure how responsibility is assigned. It's pretty common for wingtips to collide during ground-handling, which grounds both planes.