This whole thing is silly...
Here's what I think;
Some one curses. Your first option, the right option, is to click that little exclamation point and report the post. Instantly it goes out to the mods/admin and they can sneak right in and clean up the language. It is over with it, there's no argument, the thread can go on peacefully, and yet there is no longer any inappropriate language.
Some one curses. Your second option, the wrong option, is you decide to take moderation into your own hands when you have zip power, and decide you'll post a lovely little comment preaching this as a family site and that their language is highly offensive and they need to cut it out right this instant. (Or whatever you feel inclined to say.) Guess what? Curse word(s) are still there and now the whole thread is disrupted. Suddenly an argument arises and now two or more members have a large disagreement and we have bad riddance amongst them. What does that solve in any way? Now the child (if we're directing this thread towards "family friendly") sees the curse word(s) as well as the disagreement and they're receiving that bad influence.
It's simple... Just click, and you're done. It's not anyone else's job! So please, no more arguing. Let's all get along and let the mods be the "bad guys"!