One reason I dislike such digital ID schemes because I can't actually tell what information (or metadata) is being forked over. Even if it does purport to show me, I'm just supposed to trust what it says?
No thank you. A piece of paper provides a common format that's easy for both me and the official inspecting it to understand.
Honestly I don't see any other way. Else it becomes a paradise for forgery.
Mafias all around the world will buy expensively any valid or even used identity document just for this purpose, i.e. to study it and perfect their forgery skills.
The process you witnessed is a remnant of the past, a feature of the necessary transition period, and I hope it disappears soon, because that's a giant gaping security hole.
Thanks to all those biometric data, in case of a problem, the process will be much more reliable using the database than using old fashioned paper IDs.
Also, all these tests are very fast to perform (excepted maybe DNA tests), much quicker than the unreliable administrative cross-checks that were performed until now when there was an ID issue.
Like the information on my visa application, or the fingerprints collected at that time, or my travel history, hotel stays, and so on.
Data does not have your be "in the passport" to follow me around.
Note: USA "paper" passports have included an RFID chip since 2007.