WotLK: LFD
Cata: Ruined Eastern Kingdoms and Kalimdor look permenantly.
MoP: CRZ
WoD: Sunsong Ranch was popular because it was finally like players had a home. So blizzard kneejerks and gives us a fricking town with it's own industry.
Class pruning.
Legion: More class pruning.
BfA: Cringey fanfic level story writing. RNG added to the RNG's RNG for more RNG.