It started off to a rough start
First two weeks in, already people disappointed and unsubscribing.
WoD, the least favorite of many WoWers...at least most people enjoyed it for a month or two before they were disappointed
BFA takes the cake.
Most negative player feedback I've ever seen. Not just on WoW official forums, but WoW reddit, MMORPG.com and a lot of other places are filled with people disappointed with BFA. Joking about how its an early access expansion. Joking that Blizzard is an indie company. Mass posts of "I quit" posts. Sure official forums always were negative in tone...but WoW reddit? Even during the WoD era I didn't see the mass amount of negativity on WoW reddit...almost always a bastion of positivity for WoW. Even MMO champion isn't very positive for BFA.
By far worst expansion Blizzard has ever released. Sure some people like it, but people also liked WoD so that isn't saying much when the overwhelming opinion is negativity.
But...people did say...only WoW would kill WoW.