Retractions damage their credibility. I can think of no reason media would bring that on themselves.
The initial fake ‘story’ gets prime headline or top of the hour coverage.
Their retractions get run in section ZZZZ, page 12184 or in a brief 4 second soundbite at the end of a broadcast. They’re used to (and indeed counting on) nobody noticing or being easily able to explain it away.
New Media is focusing an electron microscope on them now. Dinosaur Media doesn’t know what to do and keeps on with the same thing they’ve always done because it worked for them before.