Journalists and news media, bound by the respect and principles of their profession, fulfilled this function in the past. There seemed to be a time in the past where division between reporting and editorials were more separate. We've destroyed the institution of news media without a good replacement; now people are taking editorials (people's social media posts) as the equivalent of news.
> Is it even necessary for free speech to directly result in a happier humanity?
If not then what is it worth?
> What if it simply preserves the conditions that we need for progress
I'm simply not seeing how social media after a good 10 years of it is progressing anything other than the profits of its owners.
It is nonsensical to claim social media destroyed the news media. It was already dying before the internet let alone social media. To put blame on it is a blatant lie from the losers of the old era who got regularly dunked on by bloggers and forum posters in basic fact checking.
Early wikipedia "not suitable for reports" clearly did a better job. They didn't catch up with the internet until it got basic enough for them to follow it with Twitter.
Is it even necessary for free speech to directly result in a happier humanity? What if it simply preserves the conditions that we need for progress, or merely keeps us from sliding backwards? Would that be enough to make it worthwhile for you?