Is it too late for every classic zone to have its own dungeon?

The game has come on in leaps and bounds since classic. We have the Cataclysm world now which is bordering on or surpassing the actually life of the initial classic zones. 

Would it or could it be too late to add a dungeon to each zone from classic WoW?

Levelling now has been given many ways to expedite the process to benefit those wanting to hit end game as soon as possible, but there are still those who take end game breaks to experience the journey once again as a breath of fresh air.

Each zone now basically has its own self contained story line which gives you the breadcrumbs to drop right into the next level ready zone. But what if each zone had its own dungeon to cap off the arc?

 

Please Help !
Thanks !

I didn't find the right solution from the internet.

References:
-http://www.mmo-champion.com/threads/2277712-Is-it-too-late-for-every-classic-zone-to-have-its-own-dungeon
-Case study examples