What does FFXIV lack?

[Shurrikhan]

They used to be interesting, ironically enough. Trash isn't anymore because it's encounter designed for older battle mechanics which have been 99% weeded out of the game at this point.

Agreed, I think? but only if you mean general battle mechanics (typical vulnerabilities, mobs just not being outright immune to heavy/bind/pacify etc.) rather than anything specific to those trash in particular.

I've been playing since 1.x, and even as far back as ARR, the only thing allowing for interesting trash was hyper-optimizing among Enmity, compositional variance across earlier levels* (especially, say, levels 30 to 40), party DoTs, and sequenced oGCD stuns, scarcely anything to do with the trash itself (all of which remain unchanged). Even by the time Doomspike could be acquired, most was negligible outside of tank-less runs.

* This included things like mass-DoTing, a BLM AoE Sleep (which didn't break from anything other than direct damage back then), and then nuking enemies one at a time in order so that neither heals, tank stance, nor any further uses of Sleep were necessary, for a gain in total kill-speed on fewer than 4 targets, or fewer than 5 if a member lacked AoE (say, DRG before level 40); having Bards kite the melee units in circles while tank dealt with the ranged mobs; using SCH as DPS for the Cleric Stance and greater Maim and Mend trait while a SMN healed and tanked through/via Titan and/or all party members kited melee enemies via Miasma 2; etc.

What few other things existed were almost solely to activate short casts (such as crocs' caudal swipe) to offer some extra indirect mitigation to the tank or just briefly holding an oGCD stun to use it on a mob instead when they'd attempt a special attack or, lacking any such opportunity, an AoE attack that'd otherwise deny safe access to uptime.

Even if they aren't asking for Savage-tier specifically, they're still nonetheless asking for everything to be made harder and want everything to be a boss gauntlet.

The group I've seen most commonly requesting harder normal content over the last 12 years has consistently been those who want dungeons to "feel more like real dungeons" -- a return to the likes of pre-nerf Pharos Sirius and the relative difficulty of Coil rather than something wipe-proof or reliance upon DDR memorization. They're... almost the exact opposite of those who want everything to be a boss gauntlet, and I've yet to see any Savage raider demand that the likes of normal content (the only non-boss-rushes of which are literally dungeons and ARs anyways) be even more like boss gauntlets.

I think Deep Dungeons is the only time people seemingly "tolerate" non-boss enemies, but only because most of them are mini-bosses themselves with how quickly they can destroy you, and people probably still treat the actual bosses as the highlights of their runs, not the stuff they had to "put up with" in-between. I wouldn't be surprised to hear if people dislike mob pack FATEs/CEs in Occult Crescent and prefer the boss types

I wouldn't be surprised, either, but that's because all the ways we could mechanically leverage interest out of trash before via our kits have been removed. We no longer have AoE specialists, burst specialists, opportunities to kite, reasons to focus down certain mobs, etc., even outside of the disorganized churn that is OC FATEs, so why would anyone prefer what is absolutely barren gameplay over merely shallow gameplay?