The truth of a view is more important than whether or not it's abhorrent.

Amen. But the LW Terms of Use state:

You are explicitly prohibited from: [...] Posting or transmitting content through the Website that is harassing, threatens or encourages bodily harm, constitutes hate speech, or advocates for the destruction of property;

This case went beyond LW's usual attitude toward debate; this was explicit advocacy of violence, which should always be treated as Serious Business.