> People care a lot about what is written online.
Using the word "care" here is a particularly interesting word choice to me. The real problem is not the fact that wrong statements exist online that's a problem, it's the fact that people care or believe them that's the real problem. So how do we get people to care less?
I look at your post, and see a goal-oriented rather than a system-oriented approach. You see an injustice happening, and want to put a law in place to stamp it out. That's all well and good, but what about looking at the problem on a systemic level? What if the very acts you want to put in place to help people (strong anti-defamation protection) makes the problem you want to work against even worse?
My theory that I've been running with for years is that the existence of strong anti-defamation laws psychologically makes people think something like this whenever they see something crazy online: "This wild claim probably has to be true because it's online or the person who posted it would have their pants sued off otherwise." The stronger the anti-defamation laws that exist, the worse this psychological problem of believing nonsense online gets. IMO, the mere existence of strong anti-defamation protection makes masses of people shut their brain off and believe almost anything dumb online.
Personally speaking, I strongly believe we should consider the opposite, systemic approach. Let's conduct a thought-experiment. How would truth and defamation work in a society with non-existent or very weak anti-defamation laws? Would wild claims be made online daily? Of course. But who would believe any wild nonsense they saw online without verifying it if anti-defamation laws were very weak, or didn't exist?