To the first: Well, yes and no. I remember reading on the WoW forums the Devs saying this same thing. Whether they DID IT OR NOT was a matter of debate, but they said that they tried to actively engage in and take feedback in threads where people were making and discussing suggestions, not merely saying they hated a thing or were bored, etc. When you're making detailed suggestions ("add more DPS buttons" isn't detailed, "SCH: Add Miasma and Poison as two more DoT spell lines. Add Bane (spread) and Fester (damage based on active DoTs). Have Art of War inflict a DoT and either a Heavy or a Slow (heavy might make tank positioning more annoying for them; in other words, old Miasma 2 just with another name and some tactical effect, as befits a SCH). Remove Energy Drain, have Lustrate upgrade to be a heal + shield (so you can burn excess AF stacks on it and the shield will actually be useful, something akin to "Divine Benison, the Aetherflow ability"), give Sacred Soil a Shadow Flare effect. I think collectively that would work well. Remove Dissipation, having it instead be some lower level ability to be a proto-Seraph that upgrades to Seraph at 80. Maybe something like "for the next 20 seconds, boosts the potency of all Eos's spells or adds a shield for 50% of the amount healed, something like that. Either scrap Faerie Gauge or...make it actually useful. I was hoping they'd remove the CD for Fey Blessing and make it just cost 30 gauge, since that way I could use it for burst AOE healing...but instead they kept the dumb CD. I'd either reverse that or just delete Gauge and make Fey Union just a powerful HoT like the one SMNs get when Phoenix is out that you can just fire off on the tank and forget about it." IS rather detailed.)
This doesn't mean they will DO those things, especially if they have a specific goal in mind (e.g. "DoTs are taxing on the servers and there's a maximum that can be placed on bosses, we want less of them not more of them"), but it does mean "Okay, we see that players find X fun while finding Y boring".
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To the second: Yes and no. To some people (most people?) things SHOULD be easier and easier as you get better and better at them. Imagine if writing a paper was as hard at 30 as it was at 5 when you could barely even think of how to spell the words you were using. But some other people want things to be consistently "challenging" to them. It's a different mindset, but both exist simultaneously.
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To the third: More or less agreed. One problem is that camp WAS once catered to (exclusively), which cased a ton of problems. In SB, they kind of catered to both groups (SMN and AST were complex, WHM simple), and the complex players complained endlessly that they wanted to get more REWARD for what they were doing. "not being bored" wasn't rewarding in their minds, they needed to also do more damage. Since the Devs were balancing around healers doing a given amount of damage in line with each other, that was out of the question, so instead, they nerfed complexity to end that argument.
If we gave, say, SCH (say DoTs) and SGE (say RDM's caster rotation with each damage spell healing via Kardia) and/or AST a more complex rotation now while leaving WHM and maybe 1 of the others as simple, would that not lead to the exact same issue of complaint once again? I call this the "This is why we can't have nice things" problem. "I don't want to be bored" VERY QUICKLY changes to "I should be rewarded since I'm 'working harder'", even when said person ASKED to work harder! I think that's the tightrope here.|
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And no, the answer isn't just to cut off the players that want and enjoy the simpler rotations from the game - they make up a majority of the healers. The reason that they even went that way in the first place was because of rampant healer shortages and people saying healing was too hard while non-healers also complained that healers weren't doing enough damage or Cleric Stance dancing enough to their liking.
As I've said many times before, the reason for all the "dumbing down" changes were because, in one way or another, the community asked for it. Either directly ("Healing is too hard and we can't find healers! Make it easier!") or indirectly ("We have to do more work than WHM and do less damage! If we have to do more work, increase our damage!" = "so now you all have less work and simple rotations! FIXED!"; "Healers don't use Cleric Stance enough/Healers don't cast damage spells!" = "Now Cleric Stance is removed (after a brief time of being a short duration CD) and healing is so minimal there are plenty of GCDs to use the super simple healing DPS rotations! FIXED!"), and this has resulted to the situation we're in today. NOTE ON THIS POINT: This isn't JUST healers. This includes Tank and DPS roles and Jobs. Not ALL, but MANY of the changes we've seen to FFXIV, and the bulk of the homgenization and dumbing down, came from the community asking/demanding it, either directly or in a "corrupt-a-wish" indirectly way.
It's like 343 Guilty Spark said to Master Chief in Halo 1 "You were with me every step of the way as we managed this crisis. Why would you refuse to do what you've already done?"