I agree that complicated mechanics are unfun with pugs yet too easy / boring for coordinated groups.
It's too hard to find pugs who can do EX/Coil mechanics. When the fight is over, there's no satisfaction or fun, only relief.

If FFXIV doesn't want to make hardcore content that fewer than 10% of people play, then make both hardcore and mainstream versions. Echo isn't enough. Nerf the mechanics that are too tough for mainstream and turn the fight into "you can overgear this to make up for your lack of skill".

Or keep EX and Coil for hardcore, and make other content for mainstream. But don't expect to pull mainstream players along with just a buff, then wonder why they quit because they're not having fun with mechanics.