Like, I could conceivably take photos of people I meet, store those photos along with notes in the iOS notes app (or even a contact app) then create a panel of those photos so that I can tap the right person and bring up those notes when I see them again. AR would simply make this easier and faster. Unless the AR camera was hidden it would not make it different from a privacy perspective.
That's the thing. The privacy implications are different at scale.
A world of FOSS tools, where centralized ID databases are heavily restricted or banned, and people are using facial recognition technology on people they encounter in their lives and tag, that would be fairly harmless, perhaps even doing much more good than harm.
But it's not going to play out like that. How many of us run speech transcription software on our own machines, and how many of us use a remote service?