There's already a spec for this (ISO/IEC 18013-5) and it's been implemented in a variety of jurisdictions. https://en.wikipedia.org/wiki/Mobile_driver%27s_license
The person gets to see what information the service is asking for and can approve or deny. This'll likely end up being the future of how citizens access government services online.
That's more for age verification and prove of identity, especially in the real world. It's weird that the wikipedia page is talking about drivers license, because I have the Austrian app and I use it with my normal ID card.
To access government service we have something different. Here in Austria it's called ID Austria and you sign with an app when you try to access government services, but also others like health insurance etc.