The problem is that Trump stories, good or bad, are the only stories about Republicans covered by the mainstream media. You might see Romney, Kasich, or Haley as more reasonable candidates, but they can’t get any traction. The media WANT to focus on the Republicans who are loose cannons, to make whatever boring candidate the Dems run seem more attractive. That strategy worked with Sleepy Joe Biden, and only backfired with Hillary because she was disliked even more than Trump.
