During WOTLK fighting vs Scourge,Lich King and Scarlet Crusade was way more epic and intresting than fighting vs Orcs during WOD/MOP represented by Garrosh and Iron Horde.
WOTLK had 12millions subscribers and MOP had only about 7 millions (both MOP and WOTLK had bots, but during MOP there was probably much more bots and ppl who was botting on multiple accaunts)
When most villians are X race and all good guys are Y race in game its pretty lame and morally wrong.
And also making Tauren vs Orcs fights/conflict makes almost no sense, Taurens are first or one of first 2 races that joined Orcs and became their allys,
Playerwise in game i seen some Orcs and Taurens who hated Blood Elves and Night Elves, but i almost never seen Orc players who hated Taurens. It would make more sense making Orcs and Taurens even bigger allys then making stuff like Garrosh vs Cairne fight.
Orcs was peaceful shamanic race before Legion invaded the world, and it was not Orcs who summoned Burning Legion to the World but High Borne Night Elves.
"The Night Elves' reckless use of magic drew the Burning Legion into the world and led to a catastrophic war between the two titanic races."
http://wowwiki.wikia.com/wiki/Night_elf
"Burning Legion became attracted to the world of Azeroth due to the reckless use of magic on that world. The Highborne's reckless use of magic sent ripples of energy spiraling out from the Well of Eternity and into the Great Dark Beyond."
http://wowwiki.wikia.com/wiki/Burning_Legion
But Orcs getting alot of the hate.
I understand there is few players obssesed with faction pride and hating Orcs, and those players was happy to see that alot Orcs was portrayed as bad guys, but those players are minority of Alliance playerbase.
And alot Alliance players who doesnt care about Horde/Alliance faction pride was saying that lorewise fighting mostly Orcs in quests/raids is boring.
Also think of players who was maining Orc character for years, i dont think that killing other Orcs for them was too fun, even if those Orcs was not Azeroth Horde but Iron Horde or Garrosh Horde.
Also it was wrong that during MOP Orgrimmar was conquested by Alliance, but Stormwind wasnt conquest by Horde before. Its unfair that there is Hordebreaker and Conqueror of Ogrimmar title, but no Conqueror of Stormwind title or Alliancebreaker title.
During Vanilla Horde and Orcs wasnt the bad guys.
Also according metacritic WOTLK had much better rating than WOD and MOP
http://www.metacritic.com/game/pc/wo...urning-crusade User Score 7.8
Generally favorable reviews based on 749 Ratings
http://www.metacritic.com/game/pc/wo...-the-lich-king User Score 7.4
Mixed or average reviews based on 874 Ratings
http://www.metacritic.com/game/pc/wo...raft-cataclysm User Score 5.5 Mixed or average reviews based on 916 Ratings
http://www.metacritic.com/game/pc/wo...rds-of-draenor 5.9 Mixed or average reviews based on 1078 Ratings
http://www.metacritic.com/game/pc/wo...ts-of-pandaria 4.8 Generally unfavorable reviews based on 1226 Ratings
Some gameplay improvments like Toys Tab,Cross-faction Auction House, Cross-Battlegroup Arena was great and made Arena/Random bg queues faster but Lorewise and storyline wise WOTLK Raids and Quest chains was better.