Social media (and Google, etc.) have pumped out fake news for so long that I now suspect that most people are extremely sceptical about *everything*.
So now we have a situation where trust in all institutions is lower than it was in the past (I'd guess: a decade or so back). No one trusts the media. No one trusts politicians. That 'customer review' can't be trusted. No one trusts 'experts', in any field, anymore. (See: Antivaxers, etc.). Even photographic evidence viewed with your own eyes is probably fake (thanks Photoshop), and no one trusts that anymore. Nothing can be trusted.
That's what's killing democracy, and indeed, society. The trust has evaporated.
Yes, I do think tech companies need to accept most of the blame for that.