Where would John Petrucci be without Dream Theater?

[ZeppelinDT]

Maybe Ozzy would have snapped him up. He would've joined some band for the exposure then done a Satch or Vai.

Hey, he isn't THAT old, give hi ma few years and if Dream Theater goes under (doubts yes, but you never know) he could be the new SatriVaini

Ozzy has a reputation of finding young hotshot guitarists, so if DT never happened it's a possibility in an alternate reality. It's not one I'd want to live in though.
To paraphrase Gene Simmons "In a world without DT, It's no place for me"

During their "singerless" phase, didn't DT actually send a demo to Ozzy in an attempt to become his backup band?