While many will of course still be culture shocked when we do have definite proof of
intelligent life from elsewhere, especially certain religious groups, our literal centuries
of fictionalizing what aliens might be like and how we might encounter each other
will have done a bit of good to make the public at least aware that the Universe
isn't designed just for humans.

That undocumented quote you posted seems rather dated to me, hoax or not.

How we come across ETI will be the deciding factor in our reaction and what will
happen to humanity as a species and a culture. Like many things in reality, our
first detection of alien life probably won't go as we think, though SF has certainly
hit upon many diverse scenarios.