It was launched for older people who do not have relations they can speak to regularly, for one reason or another. It was so well received that there was clearly a need for it.
Those of us with family at hand and the confidence and energy to get out there and speak to the neighbours if not, should not decry something that offers companionship to others.
I don't think it is quite another Samaritans, for people in extreme depression and distress without help, though it could be a way of contacting someone in an emergency. It is more a source of a friendly phone chat with the same person at pre-arranged intervals. The volunteers who do the calls have a list of regulars, and each regular is on the list of more than one volunteer, so that if one is off sick or on holiday, there is still a known voice to hear.