Take a physical card and a phone. Throw both on a busy street and let them stay there for a few days.
Come back and find them stolen.
Which one is easier to reacquire? You can just walk to any store, grab a phone and restore it from a cloud backup (or even a local one if you're so inclined).
To get a full-on ID is a huge hassle of reserving a time to the police station, them asking you weird tidbit questions about your life and parents to make sure you are you and then you'll get an ID in 1-3 weeks depending on how busy they are.
The type of card we're talking about here is not the American driver's license kind that every teenager seems to be able to forge according to the movies. This is a proper personal ID card with holograms and security measures.