The Horde’s rationale was “capture Teldrassil”.
Sticking with Sylvanas after genocide is the problem.
You’re right, though. All we have is data on those who have spoken. I will say, I know several people who do like the 9.1 cinematics and beats. But, for each one who likes them, I know someone else that doesn’t. The most optimistic… I guess about 50% of the playerbase. That’s my most optimistic, which implies that, really, it’s likely over half, more than one out of two, of the playerbase didn’t like 9.1’s story.
Or, at the least, perhaps this qualification has merit: of those who care most about the story, the story has not been well received. I’m sure most of Warcraft’s playerbase is simply happy to get some video detailing story elements. However, just as I don’t personally care about how fun the next raid is, they probably don’t personally care what happens next in the story. To me, WoW is a story with a game attached, to them, WoW is a game with a story attached.
Regardless and either way, we don’t have data to support either claim, so it’s a moot point. All I can say is that, of the vocal fanbase, the reception has largely favored the negative than the positive. It’s worth taking that with a grain of salt - giving it big error bars -, but… At least directionally indicative.
EDIT: Additionally, a good story doesn’t have an optimistically 1:1 Like:Dislike ratio, which is what’d you expect of a “half the fanbase liked it”. The fact that we have to have elongated discussions on “is this good” is at least indicative that it isn’t that great.