Well, their widespread acceptability seems to be declining, as indicated by all these articles and quittings lately. Presumably widespread quitting of users would only come after, not before, some high profile upsets and mistakes.
And # of Advertisers and Revenue are proportional to how people think they're doing, not how they're actually doing, and would presumably only decline after a mass exodus.
i didn't make a strong claim that they are declining right now, but sentiment really seems to have taken a dive in the past few weeks, which could be a leading indicator of a decline.
(and your linked article is 9 months old talking about even older data so is not really relevant to the current state of affairs.)
