The 'why is this news' sentiment is understandable, but people underestimate how much this kind of public /mainstream attention can matter when it comes to action being taken.

The only analogy I can think of is smoking. IIRC there was already a consensus about their dangers in the fifties, but it took decades, in part by strong lobbying efforts, before the public accepted/internalized this truth.

Similarly, the #metoo thing might cause shrugs among those who were in the know for a while, but I'm sure the public outrage will have lasting effects. I mean, Cosby's crimes were an open secret until suddenly it wasn't (a comedian went viral, or something like that?).