Because other lies are dangerous and I don't trust people to think critically. We also don't have a direct democracy and maybe that's what saves us most of the time.
There are solutions here that aren't predicated on that decision, such as shutting down the dangerous avenue to all data equally (though that would break the Facebook ad machine).
The point that a lie in this context can be societally dangerous is still very relevant. Next up is the frequency / commonality of these dangerous lies.
