SOME Players want to play that way. And that is their prerogative.
Most players do not give a hoot about challenges or "improving".
I agree that it sucks to play blindly. I wouldn't call myself hardcore in any way but I still like to see what I am doing.
Frankly put though: on a personal level, FF-XIV is pretty easy, even in savage. It's infinitely more important to play the mechanics cleanly than it is to do ERMAGAAAWD-DPS™.
The difficulty comes from having 8 people perform well enough for 10 minutes to kill the boss.
Most parsing is for parsing's own sake, comparing your virtual private parts to those of others. If that's fun to you: knock yourself out, personally I can't be arsed to perform beyond what is demanded by the actual content. I have better places to put that kind of energy than a video game.