This is a repeat from another post, but it's worth repeating.
The reason I tend to look at the best development of the original World of Warcraft as 'half of Wrath' is because the pinnacle of the game's design was when Ulduar launched. Not only was it worthwhile in terms of raiding play, it had legitimate lore importance and was built to see the variety of class design be utilised via means that had never been seen previously. This was also when the team that had effectively built the game to that point was moved on, and a new group (essentially the current group) took over.
Wrath didn't start with group finder, it's only 'weakness' was Naxxramas; which ended up being the most popular raid the game had seen to that point, in terms of participation. The greatest single encounter ever designed, in my opinion, was Sartharion - built by Scott Mercer as a means of testing how hard modes can work prior to its zenith when Ulduar opened. Don't forget that specialised professions still existed at the start of Wrath, something arguably at its best during Outland, and something that was then utterly abandoned when the new team, led by Greg Street (who had operated during Wrath's beta), delivered the wonderful, the amazing, the fabulous...
Trial of the Crusader.
Difficulty modes were created, rather than using a scaling system. Gear inflation and deprecation started to get worse. Specialised professions were abandoned. Multiple classes started to get grossly simplified. Scaling encounters and hard modes were abandoned. The communal aspects of progression started to be heavily lightened. Loot itemisation started to be collapsed.
The dungeon finder was added.
It's relatively clear that the overwhelming majority of the first team, that got us to Ulduar and arguably would have been there for Icecrown, weren't replaced with a group that viewed things the way they did. Kaplan and Chilton were replaced by the likes of Nervigg and Zierhut. Scott Mercer was replaced by Ion Hazzikostas. Greg Street took charge, supported by the likes of Corey Stockton.
I'm not arguing that Wrath was hardcore, but my stance is that it was as casual as it ever needed to get. As an expansion, it was a huge success so, for some reason, the new design team thought utterly destroying the raid community (particularly server-PuG wise) moving into Cataclysm was the right idea. You cannot build a certain community, re-create their game in the opposite direction, and expect them all to stick with it.
Remember Greg Street's
"Wow, dungeons are hard!" post?
Remember how long it took
before they were all gutted in difficulty?
The problem was considered so severe, and so dismantling of the group PvE community,
that LFR was created for tier 13.
Ultimately, this is part of what drives the desire for Classic World of Warcraft. It's why I can't wait to see it. It's not pure nostalgia, it's the understanding that the game was originally built to be rewarding, not just to throw around rewards. This difference is so subtle, but
so important. Class uniqueness, player options, system depth and rewarding challenges were the norm, rather than (at
best) the last rung of a seemingly endless settings ladder. For crying out loud, raids now have LFR, Normal, Heroic, Mythic and Additional settings. Dungeons have Levelling, Level Cap, Heroic, Mythic and Mythic+.
From one setting, with a scaling difficulty that was pinnacled by a single encounter in the Obsidium Sanctum, to five settings across the board. It's ludicrous, needless, and indicative of a design collective that just doesn't have the talent that their predecessors had, and hopes that showering people in rewards will be enough of a dopamine casino to keep people around when they don't have buddies that will.
I get lots of people will disagree, say I'm wrong, or troll what I'm saying. I'm just trying to be honest, tell you what I consider the most important aspects, and why I think Classic is what our community finally needs. Sure, it'll see a nosedive after the initial spike, but it'll then stabilise and steadily grow to a reasonable plateau.
I can't wait.