Since Trump has been elected, media companies (both left and right) have had record viewerships and profits. Polarization is everywhere and organizations like The NY Times, Fox News, and CNN benefit from identity politics: the more outrage, the better. I’d probably argue that Trump only got elected because of constant coverage in mainstream media for his constant absurd comments.
Now, imagine that boring old Joe Biden wins. He is the prototypical old boring politician. A huge portion of people will go back to not caring about politics and not caring what Trump says or does. When President Trump tweets something crazy, it is national news. When post-presidency Trump tweets something crazy… will anyone care? Do we actually care what Jimmy Carter, Bill Clinton, or Obama say 1/10 as much as we did when they were in office?
TLDR: The media benefits from polarization and Trump’s unpredictability, ergo, they secretly hope he wins, as it leads to more profits and more opportunity to spread propaganda. The enemy of Trump is a powerful image to rally around (and raise money) and they benefit more by keeping him.