It was an incredibly visible and influential accusation that seemingly came out of nowhere from arguably the most prestigious newspaper in the country, and legitimate businesses like PornHub and MasterCard are terrified of brand association with child porn and sex trafficking -- if those stuck, it's corporate suicide.
You're right that most opinion pieces don't make a shred of difference. But this particular one, because of the seriousness of the allegation combined with its plausibility, did in a big way.