This is such a worthy mission, and it addresses a real problem that is becoming more and more salient in our modern society. As populations age, people move to cities, and lifespans extend, loneliness amongst the elderly becomes a real problem that is invisible to a lot of people.
I actually recently read an article describing a new tech gadget to help elderly at home order their groceries, medicine, and other tasks, all with a very simple interface that anyone could understand and use. Curiously enough, the users of the device kept contacting customer support asking questions, and the design team of the device was puzzled as to how people could be so confused and need so much help with a device with literally 4 buttons. Well, turns out that the real reason people were contacting customer support so often was that they were lonely and just wanted to chat with another human being.
I am from a small town, and my grandparents (80 and 86) are healthy and part of a community. They live in the town where they grew up, and have plenty of friends, family, and activity around to be happy. It's a fortunate situation that is much harder to recreate in cities, where family/friends may live very far away, and the pace of life is faster. I think it's a great idea to find innovative solutions for cities as described in this article.
The same way we have coworking, flat sharing, ride sharing, and other arrangements of resources making the modern world more flexible and efficient for a lot of people, cohousing could be the next trend that helps combat loneliness and house affordability problems for a lot of people.