It seems impossible to hold a strong opinion on this without reading the article, and in particular, seeing how it is sourced.
The elephant in the room (which Greenwald barely acknowledges in this essay) is that many mainstream news organizations have concluded that the evidence for this story was too weak to publish, and some believe it was fabricated by Russian intelligence. If Greenwald has evidence to the contrary, great, the world wants to see it, and (claims of "censorship" notwithstanding) he will have no trouble getting the word out. If all he has is salacious hearsay, it's hard to fault his former editors.
The elephant in the room (which Greenwald barely acknowledges in this essay) is that many mainstream news organizations have concluded that the evidence for this story was too weak to publish, and some believe it was fabricated by Russian intelligence. If Greenwald has evidence to the contrary, great, the world wants to see it, and (claims of "censorship" notwithstanding) he will have no trouble getting the word out. If all he has is salacious hearsay, it's hard to fault his former editors.