That's only true if we get a private server like version of vanilla starting off at 1.12. If we get authentic patch progression warriors are going to be in a pretty bad state damage wise for most of vanilla and only be in high demand late AQ/early Naxx.
Protection warriors will also be in a much worse state threat wise and that will have a ripple effect throughout the game and will push classes like mages and rogues higher up on the list of desired classes due to their threat reduction capabilities. The shadow/warlock combo might even become completely unviable because of this.