> Are there any other Operating Systems than iOS, Android or Android flavors

Yes, there are many more: GNU/Linux, Windows, macOS, *BSD, etc.

This will prevent people who only own a computer and not a modern iOS/Android smartphone from accessing services and platforms.

This also sets a very strong anti-competition pressure. Which company will try now to invest on developing a new OS for smartphones if we already know users will not be able to access the most popular services & platforms with it?

Yes. LineageOS, GrapheneOS, Arch, Sailfish, various other open distros, Windows Phone, and a surprising number of random proprietary options (these are sometimes based on Android, and have some social media apps, but can't run regular Android apps that weren't specifically designed or altered for it) including for modern dumbphones. There are always more over time, too.

There's also old versions of iOS and Android. We don't want to end up in a situation where people are locked into one of only two vendors and can be forced to keep buying the newest model to use an ID app that only supports the most recent software. That'd be even worse for the environment than the current disposable smartphone culture.

Everything to do with the age verification push is corrupt and stupid to begin with. There isn't even a legitimate cause behind all this for forcing ANY app, even if it didn't also force people to buy a specific, expensive, privacy-invading American product.

as far as I'm aware, Adroid is not the same as the requirement here, which requires specific Google attestation.

There is GrapheneOS, HarmonyOS by Huawei, LineageOS for older phones and many more Android ROMs.

Additionally, Linux phones exist and are already sold in the EU to consumers, not just a prototype.

There's really no justification around limiting the OS selection.

There is also Linux, Windows, MacOS and many more operatint system not limited to phones.

> Are there any other Operating Systems than iOS, Android or Android flavors?

Like Windows, MacOS and Linux?

SailfishOS, various incompatible blends of AOSP, KaiOS, and the Mocor based OSs run on various UNISOC based dumb phones

Even in a world where Android and iOS have 100% of market share, the law (including indirect but obvious consequences of the law) should not force using them.

I'm on SailfishOS since a couple of years

> Are there any other Operating Systems than iOS, Android or Android flavors?

I remember a gov.uk team presentation. They had a usecase of someone using a PS Vita to access a government assistance program because that was the only device they had access to.

Among 450 million people in the EU there are definitely more OSes than just latest versions of iOS and Android.