Google appears to be working on support for digital ID cards including digital driver's licenses in a future version of Android. The new IdentityCredential API, spotted by the folks at XDA, may allow for a future Android-powered phone to store credentials, and even offer up those credentials when the device doesn't have enough power to boot.
The technical details of the new API are pretty complex, but the exceedingly simplified version is that this new API — which probably won't make it into Android Q, sorry — meets a set of ISO standards for storage that can include secure ID cards like digital driver's licenses. The API also supports sending credentials securely via NFC, with a "direct access" mode that could support use even when the device can't fully power on. That will require secure elements separate from the SoC, though Google has included similar hardware on its devices since the Pixel 2.
The new API can be used for things other than digital driver's licenses too, that's just one example Google provided. In more pedestrian security concerns, it also includes expected precautions like certification levels based on whether ID storage is software or hardware based, etc., which can tell developers just how secure a given device is.
For more developer-specific deets, click through to XDA's coverage, or feel free to peruse the associated commit for the IdentityCredential API yourself.