Could they do something better, sure. I am still glad to see they did something at all.
Only a few EU countries have rolled out NFC-based eID functionality (as only physical ICAO-based ID verification via NFC is a mandatory part of the EU ID card standard); those are the only ones with a viable path forward in the short term.
The app has the benefit of being free, getting a working reader costs 60-90 euros last time I checked and Linux driver support isn't great.
https://www.logius.nl/actueel/qr-code-scanner-digid-app-werk...
(Also works fine on my GrapheneOS phone with only basic integrity, also worked on microG when I tested.)