I would actually disagree, I don't think MMOs play even slightly like RPGs anymore. An RPG has some amount of decision making and character building outside of what they look like. FFXIV is as on rails as it gets.
that has been the case for most MMOs, with some exceptions like ultima online or maybe runescape. the RPG part was always more about making numbers bigger, then WoW finished it off with transplanting diablo loot on top, and the rest is history.
The playerbase shat the bed and complained harder than anyone has ever seen before, and so within a few months every last dungeon was made laughably easy to the point where you could ignore all of the mechanics and aoe-tank-and-spank it. And the playerbase loved it. Threat was made irrelevant, the tank classes began to play more and more like DPS classes, and mitigation became far less active and far more "just push this button after everything is grouped up." At the same time, WoW tanks didn't have as extreme of self-sustain as the FF14 ones do, so healers there at least spent most of their time, well, healing.
it's not surprising that a playerbase which was trained on WOTLK where taunt+aoe was the principle of dungeons, especially towards the end, doesn't want to back to scholomance.
cata also didn't really made them "hard" again, what they did was making them tedious again (which tbh was always WoWs bigger problem). no one wants to wipe on trash, no one wants to spend more time then necessary on filler mobs, especially with randoms. blizzard could've kept the difficulty, remove half the trash, rebalance rewards towards the lower cleartime, and that would've been fine. instead of sitting 90 minutes in a dungeon, you could do it twice for 45 minutes, if not shorter.
the dps tanks were another aspect of that, since you didn't really need fully stuffed out tanks, so instead of going more defensive for no gain, might as well do damage. and if you had raid-gear, with WoW's linear item progression, meant you could cheese even harder (tbf that's not limited to WoW, every MMO has powercreep and will see that effect, WoW is just the most prominent and best worst example).
I'd like a competitor to actually offer this, too. I played a bit of WoW Classic before said NEET population drove me off, and it was just so refreshing to have different abilities for different circumstances, without feeling like some of the super-niche things -had- to be in steady, continual rotation. But I mean - designing classes exclusively for your most retarded players and content exclusively for your most autistic players seems to be the paradox that modern MMO design is trapped in, FF14 being one of the prime examples.
I mention it too often so I probably come across as a shill, but ESO does that. it has it's own issues (no game is perfect) and I don't want to go too offtopic than necessary, but
for example there is no AOE taunt (as much as some parts of the playerbase whine about it). there are also no cooldowns on abilities, your "rotation" is limited by the resources you have. skills are a cross between gw1, gw2 and skyrim, meaning you have 2x 5 skills you can mix and match however you want from different skill lines + 2 ultimates each. community is chill (at least on the EU side) probably because you got a lot of boomers. no limsa ERP, I suspect people do that in their housing instance since the GMs aren't big fans of sex stuff, even in player names.
oh and gearcap with vertical progression, so hard content is actually hard. there's solo and dungeon shit from years ago that still gives people trouble today. which means you absolutely want to bring a tank who knows what he's doing and has the gear for it, and thanks to gearcap you can't cheese it (all raid gear does is give you +5% done/-5% received on damage)