I don't know where you operate
London, Paris, Amsterdam and Dublin mostly. Radio traffic is non-stop. I imagine it's no different around the major Aussie airports.
I agree that using 121.5 for mindless chatter is undesirable (we use 123.45 for that in Europe, technically illegal but harmless), but saying that it is somehow dangerous, or that an aircraft on approach has a vital interest in distress traffic that is not within miles of them, is stretching the point a little.
You should hear the crap that fills the airwaves on oceanic routes... worse than 121.5.