I don't think the issue at hand is truths and lies, it's the ability to both communicate with hundreds of millions of people easily while at the same time also being able to create smaller silos of group think with no restriction on geography.
The problem is differentiating between "information" and "misinformation" - which is exactly the issue of truth and lies, isn't it?
Otherwise, if you ignore the truthfulness of information, and judge only by the effects, you're walking a slippery slope towards censoring truth because "it's harmful".