I think there's some truth to your OP. When it comes to playing the game, I don't care about leveling - what I care about is being able to do fun parts of the game.

For my first dungeon, I have to be level 15 in a combat class.
For my chocobo, I have to be level 20.
For my next dungeon, I have to be level 25.
To see the full culinarian questline, I have to be level 36.
To see the full main storyline, I have to be level 50.
etc.

In each of these situations, I could care less about the level except that it's the gateway to the content I want to be able to enjoy.

However, I do think that many players consider the leveling process as content, placing way too much emphasis on the sense of achievement that comes with it.