XIV EW Job-Gameplay is Terrible... Why?

[Absurdity]

FPS games are boring all you do is press m1

A rather reductive comparison. The frequency and what you are doing in-between pressing the same button makes a big difference.
A majority of playing Greatsword in Monster Hunter is just pressing the same button for your charged attack but that basically never gets old, because getting that button press off in the first place and having it connect isn't so simple, the same applies to FPS games.

FFXIV however is a tab target mmo where you almost always have an ability connect at least every 2.5 seconds, there is nothing stopping you from hitting that GCD besides the boss just becoming untargetable.
To illustrate what I mean I took one of my old logs from Abyssos on Warrior. I only counted Heavy Swing, Maim and Storm's Path and ignored Storm's Eye since that's where the consolidated combo would have to branch off (unless CBU3 decides to just outright remove Storm's Eye for maximum boredom).

I had 44 casts of Heavy Swing, 44 casts of Maim and 29 casts of Storm's Path for a total of 117 casts of just my basic 1-2-3 combo. At 2.5 GCD that is almost 5 minutes (4.87) spent on just those in a ~9 minute fight, which I would spend on nothing else but hitting the exact same button after combo consolidation. Yes, I did ignore oGCDs in this because defensive oGCDs on tanks are as boring as can be and WAR doesn't exactly have a lot of offensive oGCDs.


Funny side note. Of the remaining time I also spent 2 entire minutes in GCDs on just spamming Fell Cleave, shows you how much of a joke the design for this job is.