I am actually glad the devs decided to give the content a little bit of a push. We have seen the same mechanics for years and factually, we still play the exact same mechanics now, the main difference is the way these mechanics are telegraphed.
By adding a little bit of awareness and trying to teach players to look at .. shiny things at bosses or the sides, the devs are in a sense make also create 'better' players and more people who think themselves now .. less afraid to jump into ex trials or savage content.

The main 'difficulty' comes simply from having never to watch out for anything in the past and now suddenly .. we are asked to use what we have learned in the past.
Do we have new telegraphs? Yes
Do we potentially fail to identify these telegraphs at first? Yes
Does running the content gets players used to the new telegraphs? Yes

So all difficulty will practically vanish over time. When gear also gets a bit elevated, failing mechanics can easily be tanked/healed through as it always used to be.
I feel like most statements regarding to the difficulty is just coming from first impressions, rather than actually engaging or playing the content.
Having to pay a little bit of attention in a dungeon can only be a good thing, as it raises player awareness, but this is an effect that needs a little bit of time to shine. We are coming from an age of brain dead/ignore it all.

I would be very sad, if based on the vocal minority, the next bit of content again gets designed to be braindead, as all content eventually will turn into that anyway, with a bit of time and getting used to it. Having it feel interesting in its early stages of its lifetime can only be a good thing.

In the end, it is okay to fail while learning. A run gets severely handicapped when you have deaths in the attempt, which can derail the whole attempt. But that is fine.
We humans usually mostly learn through failure, not through success.

Also this is final fantasy XIV, no patterns are random or not telegraphed with enough time to comprehend and interpret it.
But there are simply unspoked rules in the content that people are usually figuring out during their journey and are expected to be used, such as:
you can move as early as the cast bar for an enemy attack is finished, because the attach, despite of what you see, is at that point locked in place. So dodge windows become a lot larger keeping that in mind.

So TL;DR
I feel the content is decently paced and I love that change.
People should learn a bit of patience and it is okay to take some time to learn.
It is okay to not rock everything at the 1st time.
It is okay to not rush simply everything.
Please do not design content into super easy braindead again, as it will turn out this way with the passage of time anyway.