With the new ease of access to people with opinions different from your own, most people now require some self-consistent reason for not interacting with them and their views. The idea that other rational people can have differing views from our own is deeply unsettling as it allows for the possibility that our own views are incorrect.

Pre-social media, this was easy enough: the people with different opinions were just less educated or less informed, and once they became informed they would hold the same views that we do. Social media changed all that by bringing those with different views into direct confrontation where you could immediately connect with someone with different views to your own and educate or inform them.

This fails to work. As soon as we try that, we quickly realize that those with other views are already informed and have just taken a different judgement. So we're left with the problem: either our views are wrong or their views are wrong. Deeply concerning as it's just as likely to be our own views. The only solution then is to shift the blame - it's not our fault or people with other views at fault: it's that there are 'evil actors' working to 'brainwash' people. Therefore our views are correct, and it's just people with other views who have been brainwashed. Simple and clean, no need for self reflection or difficult questions.