Dungeons are becoming style over substance.

[Nethereal]

I've never understood the opposition to the bolded, coming from some quarters. It's something I wish they'd make more use of. Anyway, well put.

I think it's part of Yoshida's plan to keep everything all inclusive. Ultimate, savage, and extreme are all okay because they're 8 person content and you can largely rely/get help/carried to some degree on each of them.
Not only that but they're very far away in figurative distance in their placement, dungeons can't be compared to extremes at all, savage can barely be compared to extremes, and ultimates are their own ballpark.
Making difficult 4 man content would either be between dungeons and extremes, at or above extremes, or maybe even savage level.
This difficulty setting puts it extremely close once again figuratively to dungeons.
People usually aren't jealous of the person 50 states over that they hear about once a year, they're jealous of the person who lives right next to them who they have to see & hear about daily.
I think Yoshida wants to avoid this perceived slight the community could possibly suffer.

I've experienced dungeons in a plethora of MMORPGs now and I can safely say that whenever people claim dungeons were "harder and more interesting" in the past, they're talking pure nostalgia.

Gatekeeping, generalizing, and talking for everyone while completely ignoring the fact Yoshida has made statements talking about how people have noticed dungeons are easier and more streamlined and it is intentional.

This happens in literally every single MMORPG that exists for a longer period of time.

Except it doesn't. Don't conflate the issue with your bias.
Dungeons can and do get more boring especially when the it's the developers intention or they don't care to explore or experiment anymore because they know the formula to make the most people happy.

Same goes for FF14. I've done every dungeon in the game scaled down throughout playing and I can safely say I see nothing in the older dungeon design that would've ever made them complex.

Doing old content at minimum Ilevel 3 expansions post is not the same at all as doing it when it was relevant content. So many things have changed since.
Doing ARR dungeons on Sage for instance or any of the new classes since that dungeon was released is not going to provide you any relevant information on what it was like to do them back then, it's a completely different experience outside the song and dance.

They also had branching paths (99% of the time leading into dead ends with side story pages on the ground or a treasure chest), but that's wasted effort that only a handful of players would willingly go to.

It's called immersion.

I see a lot of people wanting difficult dungeons, but no timers to avoid the "toxicity WoW has".

And the truth comes out, scared of the big bad toxic boogey man.