The core idea is that we move to self-managed, modern, always up-to-date, dynamic contacts which are also way faster and easier to exchange.

I imagine it's also the first alternative to Facebook for people who simply want to stay in touch digitally, despite changing online and offline environments.

If Cardbox becomes ubiquitous, manual contact management for everyone you know will be a thing of the past. You will always have access to the latest contact info of your connections, always a recent photo, always access to their preferred messaging and social apps.

Anyway, this is early days and those group features are always possible in the future. :)