I don't understand where the all the EU anti-trust and anti-corruption regulators are here. _Governments_ enforcing that you have a Google or Apple account to participate in society is transparently absurd.
This isn't only a digital sovereignty issue, it's also an anti-competition issue.
The EU way is to think these things are “free” and then act surprised by the inevitable consequences five years later when it is irreversible.
Our AI gods cannot save us soon enough.
The reality of the matter is that it is virtually impossible for Europe to even begin to displace Apple or Google devices, and especially not operating systems and all the ecosystem that goes along with it.
The EU politicians are just publicly paying lip-service to "digital sovereignty" while they quietly hope this all just blows over when Trump is gone in 2 years.
My understanding is that you are not forced to use this. Sites in the EU that will be required to verify user age will be free to use any method they wish as long as they can show it is as effective as the app and it does not violate privacy laws.
Most analysts expect sites will offer multiple ways, for a variety of reasons.
Eventually when the full EU Digital Identity Wallet is available age checks can be done using that and the age-only app will go away. For the full wallet the rules explicitly require platforms to have fallback mechanisms for users who are not using the digital wallet.