Sorry I wrote a book.. do u dare read?
Something I wanted to go a little more broad with, but comes in response to this comment:
There's just no innovation. It's just a cash grab and hook at this point as they're afraid to do anything new
This grind isn't arbitrary. It's a strategy of theirs that they use to compensate for the dystopian phases that their vertical progression model leaves in it's wake.
I think they waited to release HW's Relic because they wanted to monitor post-3.0 player activity, and then use the relic quest-line to force repopulation of older content on the progression ladder: they want the player community to repopulate older or non-lucrative content. Alex N being a big example. They want that DF Queue active for new 60s to get step-stone gear towards ESO despite it's abhorrent token system and the lack of appeal it's gear has for many (most) people who have leap-frogged over it (or plan to).
The grind is their way of knocking the community down the vertical progression ladder back into fate-grinding, dungeon-running, Beast Tribe Questing, and ALEX N farming: ensuring an active community presence for newer players. I've recently lvled two alts to 55ish due to endgame boredom.. Duty Finder does the job, but still there is a tangible awareness of an empty open-world when doing content after 2.0-2.1 through 3.05. FFXIV feels dystopian at many phases throughout these and some other areas (I thought, at least. My 2nd ALT didn't get a single FC invite; unloved ;_; ).
IMO these sort of grinds are fine IF they season the vertical progression with a little sand-box, player-driven world building. Nothing detrimental to their vertical model, but something that gives an extra incentive for end-game (or I'd argue more accurately dubbed 'post-game') players to go back and do former content.
A Beast Tribe example, if interested:
If beast tribes had regional influence - Where more active Beast Tribes (active meaning more players are completing that Tribes Quests than others) gain influence that expands their Tribal Influence to surrounding zones - possibly opening up Tribe-Specific Vendors at certain regional border outpost like South Shroud's Camp Tranquil <-> East Thanalan's Camp Drybone.
So if an FC rigorously grind Amalj'aa, that tribe's influence could push into South Shroud.. An Amalj'aa vendor replaces the Ixal/Slyph vendor at Camp Tranquil and that rare Amalj'aa vendor sells rare Tribe furnishings, mount, or glamours (but these rare items also require the appropriate Tribe Ranking to purchase)..
But, alongside that aspect also add bonus rewards to Beast Tribe Quests for Tribes if/when they are being pushed out of their default territory. The bonus could be an extra 10%-20% reputation reward, sizeable gil bonus, double venture rewards, etc. (so in this example, if Amalj'aa took South Shroud from the default Ixal/Slyph, doing quest for Ixal or Slyph would provide bonus Rep, Gil, etc until either one of those Tribes reclaim South Shroud from the Amalj'aa. Further, if players keep pushing with Slyph/Ixal they could take Camp Drybone from Amalj'aa: opening up a rare Ixal/Slyph vendor at that Outpost until Amal'jaa reclaims it).
Maybe even a similar open-world mechanic for Grand Companies, making the GC-alliance of your Free Company actually relevant for example. I guess what I'm trying to say it's not a problem of new content VS recycled content. It's the model that encompasses all content. All content, new or old, are just more rungs on the vertical ladder.
And the relic quest is a very transparent aspect of vertical progression SE uses to repopulate previous phases. It's necessary, I just wish they were less transparent about it or would add open-world mechanics like the above that provide an extra incentive to step back down the ladder.
..Sorry I wrote a book.. But that's how I feel on this Questline and more-so FFXIV in general at present, had to get it off my chest.