It does, if there are smoother transitions between zones, instead of having 5-6 tiny dwarven zones you have one massive one up to the size of the new zones for let's say DF for example. Do that for EK or Kalimdor, you end up with 4-5 metazones, which is basically what expansions provide nowadays.
It won't make Goldshire or Thelsamar feel bigger for sure, and I would still prefer a proper scale up, but it would still alter how we see zones and the world in general and it could work.