N26 (Europe) requires you to have a smartphone and a SIM card. Obtaining a SIM card means that you need to identify yourself.
You can't just have a smartphone. The OS needs to be unrooted and also mainstream (iOS/Android).
This really sucks.
Furthermore, Google and Discord lock your accounts, if you don't provide a phone number.
The alternative might be to use an Android/iOS just for banking. Another Android/iOS for services such as Google (Play store).
And a Librem or any other open source phone as your daily driver. Or, just live with a "dumb phone" or no additional phone. I am not sure about the SIM card. Is it even possible within the EU to buy one without identification?