This.
BTW, in my experience it hardly played well before as well, this edition just emphasized the issues.
The so-called "Elite" army, as in "an army that is usually outnumbered but compensates for that with superior quality of units", only works reasonably well when it has a quality advantage in BOTH killing power AND durability. Eldar have zero durability advantage, which undermines the whole concept. The old codex worked reasonably well mostly because it had ways around the units' durability issues, with the most important of them being Fortune. The new codex has nerfed all of those to total unreliability, while simultaneously making most of the stuff more expensive. It just doesn't bode well... Unless updated Wave Serpents prove to be some kind of Unstoppable Weapon of Absolute Annihilation, I don't see anything that would help Eldar to survive attrition.