I don't feel like casual players or hardcore players are getting specifically catered to, but rather there are some issues with this.
a.) Anything a casual player can access, a hardcore player can access as well.
I think is pretty straight forward and obvious. By definition, hardcore players simply have more content available to them.
b.) If it's too easy, it's probably not fun.
This is where things get difficult to gauge. Content for a hardcore player is only difficult while it is in progression. Once a hardcore player has completed the content multiple times and is just doing it for loot, it loses some of its charm(at least in my opinion). Assuming a hardcore player completes all of the content in a given patch - the hardcore player is ALWAYS left with no remaining content. Honestly I haven't done a single daily quest for the beastman tribes because I'm not too interested in the rewards, and I don't expect to be challenged.
c.) If it's too hard, it's probably not fun.
This is pretty true as well, or else this thread wouldn't even exist. For a casual player who can't complete all the content, there is always more content to be cleared. However, the player might not enjoy forcing themselves to clear it due to its difficulty. For this reason, often old "progression content" gets toned down with every patch to allow more players to clear it.
Note : Difficulty can stem from a number of places. Whether it be reaction time, gear, finding a proper group, learning an encounter, etc etc etc....
However, this creates a bit of a cycle where... a small amount of content is added for the hardcore players and a small amount of old "hand me down" content gets passed on to the casual player. I don't think the average casual player will be terribly excited to down Extreme Titan when he gets nerfed in 6 months. Already, most hardcore player can clear all the content without much issue.
In all honesty I feel like both sides of the fence are hurt for content, not because SE is favoring casuals or favoring hardcore players, but just because FFXIV is a new MMO.
Personally I derive my enjoyment from the people I talk to and play with in the game.