They don't like each other. Certain elements in the Wiki community have made a regular, bordering on tendentious habit of trying to get Fox News deprecated as a reliable source. Translated into plain language that means that the Wikipedia Reliable Sources Noticeboard (WP:RSN) routinely sees editors opening discussions trying to get the community to declare that Fox News is not a reliable source and may not be cited in support of claims of fact in the encyclopedia's articles. This happens to a lot of conservative news outlets. And in fairness, some really are pretty shoddy with a history of lousy fact checking or just making stuff up. Of course one rarely if ever sees similar concerns raised about nakedly biased websites from the left.
Well today Fox shot back with an article accusing Wikipedia of blatant leftwing bias, especially in articles dealing with sensitive subjects like Communism and Socialism. Their article on Communism is actually a good example. It is an open secret that there is a cadre of left leaning editors who carefully guard the article and mobilize to ensure "consensus" is against anything too negative getting into it. Bluntly that article has been so thoroughly sanitized you could use it for a surgical ward.
Full Disclosure: I spent a good part of ten years working on the encyclopedia (close to four as an admin) before I resigned, in large part over the naked bias and hostility to conservative editors. I still think that if your looking for information on non-controversial/political subjects, it's a good resource. But the hostility towards conservatives and conservative view points is very real.