I think that free speech can only be protected while it remains civil. The rules that apply in parliamentary debate, for example, should apply universally, although without some of the specific formalities. As soon as you insult either the author or their words - insult, rather than criticise - you repeal your own right to engage in debate, in my opinion.

However anyone 'bragging' of blocking or deleting such comments, is wrestling in the mud with a pig, and is also unlikely to find themselves welcome in polite society.