Yes, the amount of division now definitely isn't unprecedented. But Silent Spring wasn't released into that very divisive part of the 60s - it was released just prior to it and that's what probably allowed it to have more of an impact. The media landscape was definitely more uniform then than now, information bubbles were much less of a thing - again, I can't imagine any book or film having that kind of impact now, that's my main point.

Another example would be the ozone layer: When it became clear in the 70s that CFCs were destroying the ozone layer we were able to make changes to stop that from happening over the course of a decade. Can't imagine us being able to do something like that now.