Why anyone would want this, IDK. What's wrong with just carrying a card in your wallet?
Plastic cards suck, for many reasons.
1. They're forgeable. Digitally-signed data is not. Sure, governments can and do implement lots of anti-forgery mechanisms, but it takes almost as much expertise to use those anti-forgery mechanisms to validate a legitimate card as it does to fake one. Approximately no one checking plastic cards knows how to properly validate them. Digital ID cards require a bit of equipment to check them, but the equipment is ubiquitous (almost every smartphone in existence has all of the tech necessary, all you need is an app), and unless the attacker can either pwn the verification device or subvert the legitimate issuing system, they're unforgeable.
2. They cannot provide data minimization. Electronic IDs enable you to provide only the subset of data that is needed for the current use. For example, if you're buying alcohol the only information the store needs is whether you're over the minimum age. They don't need your home address, your driving privileges, your name... they don't even need your birthdate. Just a single yes/no bit -- plus some way to prove that the person presenting the ID is the legitimate holder (there are some good privacy-preserving options here, but that's a subject for another post). Contrast that to a plastic card with all the info printed on the front and repeated in a 2D barcode on the back, enabling easy snarfing of the whole data set. Digital IDs are better for privacy than plastic cards.
3. They don't work online. We use various workarounds for this, but they're all far worse for privacy, requiring users to provide far more information about themselves, not only beyond what's minimally necessary for the transaction, but even beyond what the ID card has. This is because the most important information isn't so much the content of the card as the proof of authenticity.
In the future we're going to look back at the era of ID cards and papers and shudder at how bad they are.
Of course, there are also risks. The biggest one is that having an ID that does work online means that more online services will want to use that ID. This is good where it enables transactions that currently can't happen online at all, and probably good where it makes transactions that occur now but are risky less risky. It's bad where it facilitates user data collection and user identification for transactions that don't really need it at all. But IMO that risk is better managed refusing to provide ID when it really isn't warranted, and by insisting that when ID presentation does make sense that the data provided is held to the absolute minimum required, rather than forgoing all of the other privacy, usability and security benefits of digital IDs.