This presentation is a little tongue-in-cheek, isn't it?

Sailboats and rowboats had cockpits thousands of years ago. In fact, the cockswain the airplane pilot refers to was the specialist who handled the small boat (a cockboat or tender) used to transfer personnel and goods from the main ship to the shore (or other boats).

Of course, if you're gunning for the "Mile High Club," the cockpit is something else...

I thought I was interesting.

since so many aviation terms have french origin, but I guess I'll buy this explanation.

Flight deck is the term once used by the RAF for the separate, upper platform in the old flying boats where the pilot and co-pilot sat.