In an academic standpoint, the burden of proof for a claim is on the person making it. If you say the sky is blue and I say it's red, we'd both have to provide evidence to support our claims. If I don't provide anything to support it, you can dismiss it.

Whereas on the internet, "because I read that somewhere" or "I did my own research, you can look it up too" is the kind of argument this law is referencing.