No... Someone needs to stop thinking they're more mature than someone who makes a joke.
A joke that pokes fun at the people that think to insult someone's mother as a come-back to being slated.
I even TOLD you it's a joke. It was so apparent that it was a joke that you - in no way what-so-ever came out of it looking stupid. This means there's no need to go on the offense, and try to gain e-pride.
This isn't limited to you - but if you stop it ("it" meaning trying to raise an arguement out the ground for no better reason than "the hell of it"), there'll be one less person to persuade not to do it any more.
I await the resonse to this, to see if it is perhaps YOU that needs to "mature".
On a side-note, why is immaturity looked down upon?
From my perspective, at this time - becoming mature means you're one step closer to being a slave to a job you hate, and copius amounts of stress.
Edit: I'll leave the rest of that post there incase it gets anything over to you, but did you not bother to read the second line of the post? I specifically TOLD you it was a joke, and NOT to rise to it.