Literally the very beginning of the linked article:

Paul Alexander contracted polio in 1952 when he was six, leaving him paralysed from the neck down.

The disease left him unable to breathe independently, leading doctors to place him in the metal cylinder, where he would spend the rest of his life.

He later regained some very limited mobility, allowing him to leave the iron lung for very short periods; but I doubt that includes the fine motor control needed for a typical controller. You could possibly design something he could use to an extent, but it's certainly not as easy as just toss him in there with an xbox controller.