Because of lawsuits and claims that turned out to be untrue. Sydney Powell and Lin Wood made up a bunch of shit and OAN doesn't want to get sued for defamation

It is easy to proof, and was proven often, that voting machines can switch votes - they are made for the international market, and many customers want this feature. Backdoors are a must to get export licenses (the CIA gets the keys). It is more difficult to proof that the enhanced features of the machines were used in the 2020 election, because evidence was destroyed immediately. But Sidney and the news organisations claimed that Dominion itself has used the enhanced features of the machines, and that is not only impossible to proof, it is most likely not true (more likely, it was the CIA).