Hi Mulligan,
I've heard - cant remember where, so cannot verify - that it's related to a certification requirement but which one I don't know.
It certainly lifts you out of your seat at any time of day or night. We fixed it very simply. We call the cabin crew for their "cabin secure" check before takeoff and landing. This also has the benefit of not being interrupted just as ATC gives you a frequency change etc. Works well.
Of course if the CIDS is reprogrammed ( costs money) to include a "cabin ready" message on the ECAM memo you dont need it for routine takeoff and landing calls.