In addition to the money, actually using them would be hundreds of times more complex, and they don't have the provisions Google has, for example accessibility and security services (like actually stopping people stealing accounts on a large scale). All of this can be done, easily even, but it isn't. Politicians don't want to.
https://www.itsme-id.com/business/platform/identification
https://france-identite.gouv.fr/
https://english.rekenkamer.nl/latest/news/2023/03/29/digital...