Vanilla through wotlk is probably the best example of a large world with a good balance of travel tbh.

Yeah you got your flight masters or running everywhere, you've also got mages teleporting, warlocks summoning, quests and professions that offer teleports to various places, zepplins and boats to take you to more places etc. Each expansion just improved this (summoning stones at dungeons working etc).

The problem is its based around engaging with the world and players around you, the changes to make it easier from players complaining lead to teleporting queues and portals everywhere because they werent happy with anything less than instant travel.

Modern MMO players dont want to play an MMO in its original meaning and it makes this entire discussion irrelevant really.