i dunno, WoW always felt like carebear Everquest to me, but a lot of people liked that kind of gameplay and it wasnt time intensive, when i quit EQ i could play a few hours of WoW and feel like i was making progress, where in EQ it took you a few hours just to learn how to do stuff and venture outside of your home city. they should have been able to keep innovating and making the game more fun and interesting.
A lot of people that haven't played a lot of MMOs since the early 2000s often repeat the claim about WoW being carebear EQ, but it doesn't really hold up to any serious scrutiny. EQ was carebear EQ when WoW launched. There were basically three (design) things that made early EQ brutal: big penalties for dying, huge time sinks to advance your character, and open world raid targets meaning you could be called on to raid anytime 24/7/365. There were additionally a few other things that made early EQ hard that weren't really intentional--frequently broken encounter design, poor gameplay bugs, long load times, etc.
By the time WoW launched EQ had basically scaled down all of those big three things that made it brutal. WoW launched end of 2004, when Omens of War was in swing. In Omens of War like 90% of the relevant raid content (and 100% of the top end raid content) was in private instances. You'd never need to run them at 3am on a work night. As for time sinks, those were still around but things like base leveling had been increased in speed quite a bit by level 70. There had been some exp revamps, and most importantly is the playerbase was mature and the known "best leveling paths" were second nature, everyone had PL toons etc. Finally the death penalty had been significantly mitigated, they introduced Shadowrest in early 2004, a zone off of Plane of Knowledge where you could go and hail an NPC and it would summon your corpses--from anywhere in the game world, and let you rez them. No more corpse runs, anywhere.
In terms of actual difficulty, the first tier of WoW raiding (Molten Core) was mechanically more difficult than any content EQ had ever released to that point (and MC was a joke). The second tier of WoW raiding (BWL) had more complex mechanics than you saw in EQ until probably TSS or later. By BC the curve was even more extreme, there's BC fights that are harder than the hardest EQ fights that have ever been done (i.e. Mearatas, Triune God, some of the VoA Sepulcher fights, some of the Tier 2 TBL fights etc.) EQ hit a certain wall with its engine and what the game can actually do, that limits its technical complexity to a difficult level somewhere between Normal and Heroic mode raids in modern WoW.