I am astonished the cabin crew unions are not fighting this. The amount of hassle this will create, means it can only lead to aggro for the poor cabin crew.
Can you imagine it, sitting next to some loudmouth on an eight hour flight, after a four hour delay, trying to get some sleep, when at 0200hrs, 'ring ring' or some other suitably stupid nauseating ringtone, followed by lots of really loud inane conversation from the person right next to you.
The fights that will ensue over this, just don't bear thinking about. Best give the cabin crew some martial arts training.
I guess I could live with texting and E-mail, but voice calls - oh my f****** god, please no.