The fascination with the gaming controller is a bit silly.
It's not safety critical like the ability to drop ballast is. If something goes wrong with it you just kill propulsive power, resurface, and replace it. Also more engineering effort will have gone into making the controller reliable by its manufacturer than most would want to be able to justify spending creating something custom.
I just see this mistake a lot. I own this controller, and as long as it's reasonably close to the dongle, the connection is rock-solid. No disconnections as you would get with a bonafide Bluetooth link -- the dongle is paired to the controller out of the box.
It's not safety critical like the ability to drop ballast is. If something goes wrong with it you just kill propulsive power, resurface, and replace it. Also more engineering effort will have gone into making the controller reliable by its manufacturer than most would want to be able to justify spending creating something custom.