The responsibilities of free speech

I am thankful that in Western democratic societies, free speech is a valued and fundamental right. However, I think it is right that comes with responsibilities.
I am not particularly sympathetic to claims that it is fundamental free speech issue when it comes to

-pornography,
-tabloid newspapers publishing titillating details of the private lives of celebrities,
-people gratuitously using swear words on prime time television
-"art" that deliberately seeks to be offensive to religious people

These may be celebrated causes of libertarians in affluent Western countries.
Instead we should consider focusing on cases such as

Sri Lankan newspaper editor Lasantha Wickrematunge who was murdered.
He was a longtime critic of the oppressive and corrupt government that was just voted out of power.

Xu Zhiyong is a Chinese legal scholar and human rights activist. One year ago he was jailed for four years.

I found the two articles below raised important issues.

Firebombed French Paper Is No Free Speech Martyr
by Bruce Crumley, published in Time magazine in 2011.

 Defending freedom of expression in the face of oppression is one thing; insisting on the right to be obnoxious and offensive just because you can is infantile. Baiting extremists isn’t bravely defiant when your manner of doing so is more significant in offending millions of moderate people as well. And within a climate where violent response—however illegitimate—is a real risk, taking a goading stand on a principle virtually no one contests is worse than pointless: it’s pointlessly all about you.

When 'free speech' becomes a kind of fundamentalism by historian Charles Walton.

I find the readers comments on both articles rather disappointing. Many appear to have made little effort to actually understand what the authors are trying to say and simply condemn them. This simple lack of civil discourse is a worry to me.