There’s a huge amount of research, though I agree not all of it is necessarily user-centric. Where the research is user-driven, much is locked away inside Apple and Google, who both fully intend to own the identity space, alongside payments. But there’s still a lot to learn from real world implementations in Estonia, the Nordics, Belgium, Holland, and the 1.3billion people in India who’ve been issued with an Aadhaar. I’m well aware of the level of UK smartphone penetration, though not all are good enough for robust ID. My point there is, introducing an ID system that knowingly excludes at least 10% of the population is not a great idea.