Yes I am an engineer. I am also especially sensitive to this wire length thing since a neighbor borrowed my trailer, did not wrap it around the jack, and the wire dragged on the ground.  More is not always better. But I do see your point on not all towing vehicles are going to have the plug right near the hitch and  license plate like most newer trucks.

BTW I put some dilectric grease (comes in a small squeeze tube and used on ignition parts) into the female plug receptacles which seems to help prevent corrosion and make better contact, especially with the brakes where voltage changes are important. Once a year seems to do the job.

Jim at Dawn