ELI5: How are the current dungeons hard?

[Exani]

Really though as the poster above said it’s simply that they’ve changed the pacing / frequency of when mechanics occur that have thrown people for a loop.

I mean sure, but failing most of these mechanics are still not very punshing. Most mechanics are survivable with 1-2 vuln-stacks before you die, and even if you die you get revived. Max level dungeon bosses has always had some mechanics that are harder to dodge the first time you encounter them, but they are also always not very punishing when you mess it up. For me this is what defines "normal" content in FFXIV. You get to experience and learn mechanics without any punishing failure