That's because the "fake news" about Hillary was real news.

- Home brew server in her basement
- The Clinton Crime Foundation accepting funds from foreign governments while she was Secretary of State
- Clinton attempt (and in fact success) in pushing Bernie aside
- Clinton campaign approving text of articles before publishing in Washington Post
- Clinton campaign getting questions from Donna Brazille before CNN debate
- On, and on, and on

So, while there probably was some fake news about HRC (e.g., all the allegations about her health) there was enough real news about her to make people wary.