I disagree. Being exposed to the opposition's views can very easily be a polarizing force in of itself. If it's not carefully curated, in all likelihood one's exposure to the other side is going to be dominated by the more extreme parts of that side. And then it's not an unreasonable leap to go think "if those self-proclaimed moderate people tolerate these more radical elements, then they're all evil".

Which I can't necessarily argue is a wrong thought process to follow. I used to be able to pretend that the average person on the right was merely a brainwashed idiot. Now, with the internet and rise of fascism, I have to contend with the fact that they know they're brainwashed idiots and are happy about it.