Someone who's actually done all the new content here, the OP's point is completely correct and denotes a certain insight into the nature of the beast. People who play MMO's as a video game (read: almost all of them) are primarily interested in reaching max level as quickly as possible. This is just human nature, and should be expected.

Moreover, these "hardcore" fights like Ifrit are very difficult when played as intended. People shun this difficulty and find loopholes whenever they can (Kraken Club zerging and hiding behind walls for AV in FFXI, requiring Sentinel to tank Hellfire instead of downing the nails in FFXIV) and, in a game where multiclassing is expected, this desire for max level is intensified to extremes.

PLing has been an issue since people have been exploiting leves way back in December of '10. It now has become encouraged openly by the director though, and thus incredibly efficient compared to the old days. Not to mention, just about anyone can do it if they have someone who cares enough to help them out. This will eventually lead to even casual players having 3-4 50's.

However, a lack of content due to extreme ease in capping a player's level is the bane of all MMO's. Even WoW, the most successful MMO of all time, is slowly being devoured by this issue ever since leveling speed was increased via dungeon finder and highly rewarding Cataclysm quests.

That game has leaps and bounds more content than FFXIV, but it isn't relevant content. In truth the overwhelming majority of people care only for getting to endgame battles and all the shiny, stylishly epic gear. Relevant content in WoW can be done in a single dedicated night's work, just like FFXIV. It will never be any different for this game, unless the devs bring large and complicated systems like Sea and Sky back.

Sea and Sky were amazing, but not an option with the current climate of players. They could bring back Pandemonium Warden and Absolute Virtue timesinks, but do you really want that?

In summation, the problem is not power leveling. The problem is the eternal dilemma of content drought, and how the ease of achieving maximum level exacerbates it. Now, I would say "You should be making topics about our lack of endgame content instead of complaining about a standard happening in all MMO's", but this game is going to be scrapped for another in a little over a year's time. They're only going to add the most minute of changes and boss encounters to tide people over, and the best you can hope for is that 2.0 will be good.

...Just like all of those patches were supposed to save the game.