...Who don't seem to remember that almost every xpac in the past had large numbers of people complaining and threatening to unsub. Legion was very much the exception, not the rule.
Cue large numbers of people saying "BUT IT'S DIFFERENT THIS TIME!"-people said that in the past too.
I do wonder about the motives of some of these people criticizing wow. You have people like Heelsvsbabyface who bitched all the way through wod, left during Legion and now comes back so he can start bitching about BFA. Hate sells, apparently. What a great way to make living-complaining about a game that pays your wages. The same with Asmongold-complained on youtube all the way through WOD and left youtube altogether during Legion and just did twitch-now people start complaining about BFA he's back with a new video! Yeah we all know you "just have the interests of the game at heart"-you aren't just monetizing hate.
There are some issues affecting Legion but they are mostly affecting a relatively small group of elitist raiders who aren't representative of the community as a whole, who are mainly annoyed that other people who won't get boosted by their fans can have the same gear as them. They are the ultimate special snowflakes. The silent majority are enjoying many aspects that BFA got right-PVP is noticeably better this expansion, world pvp is probably better than it ever has been.
And no subs are not down. Blizzard don't publish sub numbers any more but you can get a reasonably accurate approximation by just watching the numbers in populated zones relative to a few months ago. Or you could use google trends (wow searches are a remarkably accurate, statistically significant approximation of current subs) you just see the expected small dip you get after an xpac launches. Nothing dramatic.