It would be wise to not trust any phenomenon which blows up online, given the ease of generating such a phenomenon artificially.
But I wouldn't say we shouldn't trust online phenomenon. Online phenomenon is why Obama and Trump got elected. Trump has effectively bypassed the traditional media's stranglehold on the american mind via his use of twitter and social media. And online phenomenon is why we have occasio-cortez.
As the internet gains more mind share, we have to start taking the online space more seriously.