The problem with social media defining the truth is the fact that people put way too much value in it. I don't give two flying fucks what some Face Book's executive thinks or feels as his thoughts and feelings don't dictate what's real or what's fake.
The issue is the 'majority narrative' or the 'majority consensus'. Its almost impossible to have this created - in a democracy - by a player that has 'superior means', and no corrective.
Media isnt homogeneous (200 mio put up for Trump media network, I hear..
) - every interest group could at least found a newspaper (some pretty populist rags amongst them, historically - as well as corporate papers), with public access TV - you still hold up the notion that 'everyone could broadcast over the TV network', which today roughly translates to 'everyone can have their youtube channel'.
But with social media, you have a new meta. The media company, that says, we are not a media company - we have no editorial interest, and then edits the 'major narrative' and stories out of existence. Where you cant just 'found another network' (literally impossible because of networkeffects, and at what point of 'scaling' you are bought up by a competitor), that could even have the possibility of mattering 'nearly as much'. Not even in 50 years.
At the same time people are optimizing for 'most easy consumption' (Tic Toc, very popular) -- which is the main business interest of that network. Making it so 'easy' (scroll, scroll, scroll) - all other forms of informing yourself dont interest you anymore. And on top of it, giving you what you want - self confirmation, through bubbles, and more extreme, and more questionable content by the minute, because - as an old saying goes:
The outrageous content gets watched by:
People who like it.
People who dont like it.
People who are enraged by it.
People who are amused by it.
....
So you optimize for really owning consumption patterns of people (scroll, scroll, scroll). You cant get challenged, because of network effects and amount of initial investment to compete. You have no self control measures like 'an internal code to stay impartial or fair', you have no expertise in the matter (you are not a journalistic outlet), but you are defining what peoples realities are.
Real is - what you believe. What you believe is formed by what you read (consume).
Easiest way to understand this is to try to wrap your head around the notion, that there can be multiple 'truths' on a topic, that might even conflict.
Also regardless of self-monitoring. You'd really need competition in the field. So the 'second extremist twitter' idea - is not that bad, as it looks on first, second and twentyfounth glance.
The issue there is that - what good is it, if you are creating bubbles again? That get more and more extreme. (In theory.)
So the solution is always to educate more people about concepts of 'media literacy' (what am I reading, how does this media thing work, what is "tha truth", how does media competition work, how does PR work, whats the role of a whistleblower in society, whats the role of a journalist, what role do
blogs play (
https://en.wikipedia.org/wiki/Trust_Me,_I'm_Lying (imho still the best primer)) how can journalists be held responsible (first, by learning their names, or at least the name of their publication) - if all of this 'looks like native facebook content to you', ...). And this is flipping hard, if your competitor advertises 'just scroll, scroll, scroll, ...'.
