I agree. I would even go so far as to say that all fighter games like this are boring and monotonous. You have your zone fighter, you body fighter, and so on. They all look fancy, but in the end, it's the same damn song and dance. But FFXIV takes it a step further, and not only makes it the same old song and dance, but makes it almost nearly the exact same, for every class. Hate all you want, but Bard and Machinist are perfect examples of this. Before you start in on the whole how they are different thing, let me concede that there are a few subtle nuances that you have to use in order to eek out the best for each build...but they ARE the same.
Same moves. Same abilities. Same tactics. It's literally Bard 1.0 vs Bard 2.0. Clearly no effort to make them different.
I'm not defending the OP for claiming something he hasn't tried out, he doesn't have a foot to stand on there, other than he has made this assumption based on the information he has gathered, and - whether you believe it correct or not - sticks by that assumption. It's the exact same reason you are going to disagree with me for Bard 1.0 and Bard 2.0. You will argue so damn hard on how they are NOT the same, because you believe, based on facts and evidence that you have found, they aren't. More power too you.
The point still stands however, there is very little, to no deviation between the dps available. Stand on X side for y potency. Use x ability to apply y debuff. Use generic AoE to apply damage to everything. Other games may fall in to this at it's core..but at least they have diverse skill trees to use to make them at least 'feel' different.
Edit:
I will go even further, and say not only does this game make you feel like every class is the same (Cause they are, even tanks and healers. Take the time to look at their verbiage. Dark Knight Grit, and paladin Shield Oath? Did they just copy and paste the text and change a few words? This isn't the only example you'll find, either), but the game actually DISCOURAGES you from being different.
FFXIV: "Hey did you know you can allocate points to different stats when you level up?"
You: "No shit? I'm gonna give my White Mage more mana"
FFXIV: "Yea...don't do that."
You: "What? Why?"
FFXIV: "Cause the game kind of needs you to put it in mind."
You: "Oh...ok. Well..I'll put Strength on my warrior."
FFXIV: "Yea....again...no."
You: "You fucking serious?"
FFXIV: "Well...we give you some extra damage if you take VIT..and it makes you be the tank we want you to be. So...you should probably go VIT"
You: "Fucking christ...."
FFXIV: "But at least you can...wait...no...all equipment is the same too. But there is...no wait...abilities are pretty much the same too. Oh, but you can pick cross class abi-....no...you are kind of forced to take the same thing everyone else takes. But your name! Oh god yes, your name can be hella unique in this game! One of a kind! You will stand out SO HARD with your name."
You: "...whoo"