This is an absolute LIE. The game was challenging since the ARR release. Dungeons on MSQ had challenging stuff since day 1. Sastasha, the very first dungeon of the game, was a wipe horror if the tank didn't pull carefully, if the party didn't kill the clamps fast before being overruned by fireballs, if the DPS didn't know they had to block the spawn of enemies on the last boss by standing on the water holes.
Brayflox's Longstop was a guaranteed wipe if somebody pulled any extra enemy during the dungeon because they hit the tanks like trucks, and in the final boss if the tank didn't know he had to move the dragon out of the poisons. And let's talk about the literal horror movie that was Aurum Valley.
At MSQ dungeon level there were wipes, there was challenge. There was "final sting" that would oneshot tanks at 100% if the Melee didn't stun the wasp, there was "doom" that had to be cleansed by Esuna, standing on a white spot in the dungeon or being healed. There was that one with the underground worm that required one party member to venture himself to the "danger" area to trow some meat to make the worm come out...but if he catches you, bye bye. Freaking Pharos Sirus was a wipe fest on every boss and I can keep tryng to remember stuff and it keeps coming. The game had random telegraphs for the same mechanics in diferent dungeons...or didn't have telegraphs at all (hello Cyclops from Aurum Valley).
And the raids? If we don't consider Bahamut Coils as they were NOT intended for casual players. Alexander was a wipe fest on every floor, with tank swaps, wierd shenanigans, healers having to soak lasers, while healing, while DPS gets kidnaped to 1 vs 1 an enemy while the rest are dealing with aoes, laser turrets, the boss and missiles coming from all sides.
Alliance raids? OH BOY. Nobody remembers anymore how we all needed to have a macro for Behemoth to remind people to hide behind a rock? Or that before entering cerberus we all had the A: Adds, B: Boss/Belly C: Chains converstation? That the zombie dragon of Crystal Tower was an absolute drama because people had to add slow debufs to the skeletons to be able to kill them in time or they would wipe the party. Shall we speak about the WIPE CITY of MNACH and Ozma? Who had people crying on forums and reddit for "being too hard?" because people was asked to remember 3 diferent patterns of the 3 shapes it can get? Oh boy and let's talk about Ivalice, the 1st boss saying "hi!!" with falling towers that oneshots everybody, the MATHS boss, the electric grandpa with 3 swords that had people crying from week 1.
long etc.
The game was ALWAYS challenging.