Heck, this is how professional wrestlers in general are depicted speaking. Lampshaded in MAD Magazine's 1989 movie parody Battyman, in which "Battyman" theorizes that "The Jerker" has such a wild voice because he watched too many wrestling shows as a kid.
Back in the day when he was the affable, all-around nice guy lead commentator, he'd use this voice when condemning heels' actions toward a face. An example: When corrupt referee Danny Davis fast-counted The Hart Foundation's pinfall victory over the British Bulldogs in 1987.
In 1990, toward the end of the Brother Love Show segment where Hulk Hogan was sneak attacked by Earthquake, the referees and ring officials were taking too long to move Hogan. Mc Mahon finally lost his patience and yelled, "Move it, move it!"
By 1998, as the corrupt, evil owner of the WWF (later WWE), he was regularly doing this to face wrestlers he wanted to humiliate and embarrass. Often, he'd scream at the top of his lungs "YOU'RE FIRED!!!!!" (to a wrestler that was being fired in storyline); and one time, he demanded Mick Foley — after failing to defeat "Stone Cold" Steve Austin — "GET DOWN ON YOUR KNEES!!!!!"