Not that I disagree with you, as I personally think there is an overabundance of content, which is actually the more overarching issue. They implement a lot of systems that they in reality fail to expand upon or innovate. Plenty of current systems could easily be migrated into a larger, more significant singular system that ultimately has a higher level of replayability than if they were to remain separate.
Besides, you need to keep in mind that some groups of players just simply aren't incentivized beyond self-gratification and instead need in-game systems to justify every single decision being made, as if to micro-manage how they play the game. Personally, I'm driven extensively by achievement hunting. Whether it be on this game or other games. But if I am, to be frank, beyond my own self-satisfaction, some of these systems I do actually see little value or impact in the grand scheme of things.
To put it into perspective. I have nigh on close to 17,000 achievement points, and an additional 10,000 almost on an alt character. Each with approx. 200-320 achievement tokens. Now I posit the question for you or anyone. What is the point of this for many people if they fail to expand on the reward structure? Smaller things like this ultimately create a higher level of replay value for many players, if they aren't in it for self-satisfaction. Imagine the value of achievement tokens if they managed to funnel rewards that expand beyond just a funnel for the previous (now tossed away) veteran reward structure. (You essentially get all the rewards just simply by playing the story)
To summarise; I don't really think the issue people actually have is correlated to lack of content, but rather the substance of existing content, and more importantly the significance of it in the grand scheme of things. Sure, you can get all the achievements, so what? -- Sure you can raid on all classes, so what? -- Sure, you can attain all valor in Bozja, so what? Sure, you can level everything to 90, so what?