Like you I've never seen any of this "fake" news anywhere I frequent. So I followed the links to one of these "fake" stories. Here is what I found:
From the Slashdot summary you click the link and end up at a news site called Quartz. Wikipedia characterizes Quartz as a site that "targets high-earning readers who traditionally read other left-leaning publications," a bit of the left wing echo chamber, in other words. In the Quartz story you find one link to what is described as a fake news story at a site called The Daily Signal. The Daily Single is a Heritage Foundation deal; a piece of the right wing echo chamber. The story itself is categorized by The Daily Signal as "Energy / Commentary," and — indeed — it reads like commentary, making no pretense at being news. The last paragraph:
It’s past time for the American people to stand up to Musk and demand that our legislators and other elected officials bring him back to earth before spending one more dollar of our money. He’s wasted enough of it already.
I conclude that this Slashdot story is fake; the one "fake news" story being cited by Slashdot via Quartz isn't a news story at all; it's political commentary, labeled as commentary and reads like any other piece of commentary. If this is what the left is hanging its hat on I say go for it; your delusions aren't helping you at all and I hope you continue to indulge them.