Comment by SideQuark

That’s not true. There’s been laws in many jurisdictions, including the US, applying to online forums, since before the internet even existed.

The famed section 230, passed in 1996, is an update to a section of the 1934 Communications Act, which is but one set of laws regulating many aspects of forums. Lawsuits in the early 90s led Congress to modify, but not abolish, the stack of laws regarding all communications technology.

Now that you know but 2 of the many laws affecting online forums, you can dig up plenty more yourself.