I apologize in advance if (when) this ends up being really long and disorganized. I'm, exploring my thoughts. You have been warned. Also I will be making extensive use of most likely inaccurate stereotypes of players in order to save the space which would have to be used for expressing the subtleties of all sorts of players.
Take a current PUG. Actually, take 20. Average them out. Gear levels, skill levels, effort, instance difficulty, all that stuff. Create a generic WotLK PUG. Do the same for BC. Do it again for Vanilla. They're different, aren't they?
So what changed? Obviously the instances are different. What else? I think the players changed. There are new players and there are old players who have changed. Gear changed: the stats it gives, the importance of it, how it is distributed by the game.
WoW has grown in popularity. Fire is hot. My point is that WoW is growing to be bigger than the population of socially inept, e-peen focused nerds living in their parents' basements. Maybe this was the core (it probably wasn't, though I wouldn't ignore its importance) , but it is not anymore.
The first people into WoW, based on my extensive research (I am making stuff up off the top of my head; don't bother to argue with me when I do this because I know I'm wrong. Think preaching to the choir, except more like the choir singing to the preacher) were two types: people who used to play EQ but then realized they hated it and people who used to play EQ but wanted something new. These were EQ people. They were used to waking up at 3:47 to camp a dragon or something over in the Planes of Obliv'wontilion and they were used to 34754 other people doing it at the same time (their guild plus the entire rest of the server competing; they REALLY want this dragon). They're a minority now.
WoW has run out of hopeless losers with nothing else in life. It is starting to tap into the once-impenetrable normal people market. These normal people don't act normal for MMO players. They refuse to spend five hours (make that 5-10PM, not just any 5 hours) preparing for a single kill, which will consist of the most mindless spam imaginable, though with the constant possibility of a single mistake killing everyone. Many of them want solo content and instances that can be done in an hour, or less. They aren't of the mindset to lose an entire day, or week, to a game. In other words, Blizzard tapped into a new market, but it's asking for something new in turn.
Old players with new tricks
The first players are five years older. Their lives are five years older (or has it been four years? Either way, it's been a while). A lot happens in five years. A lot of people no longer have the time for ridiculously long raids. Burnout happens. At some point a lot of people say "wait a minute... if I show up a few minutes late for work my boss doesn't even notice but if I am a few minutes late for a raid, I get chewed out and gkicked. I thought this was a game."
WoW is turning into a game rather than a second job for people with fulfilling first jobs. That was a fun blanket claim to make.
There is now a significant population that has been around for years. For them tanks, DPS, and healers are all obvious and taken for granted. The idea of a warrior that doesn't know what it means to tank, that's foreign to them. They expect to go into an instance and have everyone know their task.
In response to the new players and the changed players, Blizzard changed content, or at least didn't repeat the old content. The change from Vanilla to BC is really obvious. Where you once had instances running at least an hour, or up to an entire day if you really sunk your teeth into BRD, BC instances were short. A slow BC instance was an hour. You could spend half your time gathering the group and getting to the instance. The Mechanar is probably the most extreme example, but I can think of none that would go much over an hour and a half.
This teaches players to expect something different. They don't expect to commit any significant amount of time to a group. One hour is a long time in BC. This changes the percentage time of a wipe. When an instance takes two hours, 5 minutes for a wipe is a small change. May that an hour instance and now those five minutes are a noticeable increase in the time. Shorter instances make wipes more noticeable.
Instances just seem less wipe-causing now. There seem to be fewer mobs that run at low health. Does anyone remember the 1...2...third? pull of Scholomance, past the skeletons at the start? That was a tough one. You needed dedicated CC for some of the mobs in there, they were just too much to try to handle all at once, even if the tank could keep aggro.
Paladins introduced as to this in BC: CCless instances. Round up the mobs and burn them down. Our aggro generation for far more than enough and it was nearly equal across everything. CC wasn't needed. Focus-firing wasn't needed. The tank could put out a good percentage of the DPS of an AoE class and a single-target class stood no chance. This was a sort of reckless fun, but there was almost something I missed about tanks not trivializing everything. Now DKs can do pretty much the same; warriors and druids can come close.
People don't expect or want to spend much time in instances. They can't handle wipes much anymore. We're used to instances running smoothly. Oh sure, a wipe happens here or there, but in general, you run in and pull pull pull, loot badges, leave.
People are running instances even when overgeared. Why? Well Blizzard had a great idea: don't have people run a few instances, get to raids, and have the instances instantly obsolete. The method was to make heroics rewarding for raiders. In BC we saw the introduction of badges, and then in 2.4 the addition of incredibly powerful badge gear, apparently on par with T6. The result is that T4 and T5 players (overgeared players) have a strong incentive to run heroics. Even T6+ players still had a reason, perhaps to fill in for bad drop luck or to buy gems.
Heroics also brought PvE epics outside of raids which were not 1% drops. Epics became normal. People expected them. As overgeared people moved into Karazhan, an entire instance filled with epics opened up. Even before this, the 10->25 transition caused people to stay in Karazhan even after they were done with it.
So what does all this do to the average PUG? It makes people expect quick, painless gear with little effort.
People start expecting people to have already done an instance to qualify for running it.
People expect epics for heroics which are easy enough in blues, or even a few well-chosen greens.
People are no longer interested in helping people to get better. A bad spec means a kick rather than advice. The same for gear.
People forgot that they weren't born knowing everything. People forgot that they used to have to struggle through instances. People forgot that wipes are not totally unusual events, there's a reason that three classes started the game with OOC rezes, why druids wanted one for years, why warlocks have soulstones and paladins have DI and shamans have reincarnation. Somehow everyone turned into an elitist over the years, even bad players. They all want to be surrounded by people with perfect gear with perfect specs who have done the instance before... and don't you dare make any suggestions about their specs because it works for them so therefore it is perfect and infallible.
Last bit: I suppose this came off pretty negatively. Also my past blog posts have as well. Overall though, PUGs are not a painful experience for me. Oh sure, there are bad ones here and there, but in general they go well enough. It's usually more interesting, at least for complainers like me, to talk about the bad PUGs than the good PUGs.
I recently noticed a strangely lacking middle ground: bad PUGs that were successful. The last one was a few days ago, me tanking with a terrible hunter (the type that does pitiful damage, screws up pulls with a pet growling, and tells people to heal and res) and a rude ret paladin (or maybe it was a rogue? DPS all look the same). Oh yea, they invited and summoned me directly in, with the first boss already dead. I stayed because I was already saved and the first boss had nothing I wanted anyway. Somehow we killed the last boss, despite losing two DPS because the boss summoned the orbs that hurt you, and they just stood there. The hunter yelled for heals.
Oh hey, complaining again. Um, happy new... week? I suppose I'm a bit negative because I didn't get into tonight's heroic Naxx, despite being there last night. Apparently I have my head up my ass about blessings. I guess that means I sent a couple extra tells to ensure that the DKs had imp might. Why would I expect the person assigning blessings to know what people have? Silly me.