My understanding from people who had the material earlier that it was mostly that they could not independently verify the allegations in it and were reluctant to report something so explosive until they could. Reporters get a lot of these types of things, many of which turn out to be garbage. This might too. We don’t know at this point.
I think reporters who held it deserve credit. U.S. libel laws set a really high bar. I like to think it was done out of professional responsibility rather than fear. But, that’s the optimist in me.