But it looks like a lot of people aren't seeking the truth. In other words: "I lied to you and what will you do about it?" You might stop believing the lying person, but that means others can still make him rich.
And most people will be annoyed by preaching and you will get sued for defamation (because the liars don't care if it's not right) or bullied in any way possible. And still, despite wide recognition of lies, the liar will have support, he can even be a president (happened in my country, not USA).