Yes, your bank is shit, but this is also Apple's fault to a large degree.
There is absolutely no reason to release a new major version of your OS every year, and there is no reason to arbitrarily drop support for older devices (except extremely contrived ones, that I'm sure will be posted below). I made the mistake of acquiring an Ipad once. Its only job was playing YouTube videos in bed (yes I know), until Apple and Google in unison decided that it should be thrown into a landfill, because its OS was unsupported and the YouTube app, for no reason at all, would no longer work. Was the device suddenly unable to decode H.264 video or playing audio? Nope. But please just throw it in the trash and buy a new one - what are you, poor?!
I don't know, I haven't checked extensively but I believe supporting iphone7 is still one checkbox away in xcode (xcode 26 release notes state that it "supports on-device debugging in iOS 15 and later", which is what is installed on my iphone).
I could imagine how some team at N26 though that "supporting" more devices was too much on their plate, which I would sympathise with, but the most likely scenario to me is that some technically inept "decision maker" decided to ban older phones in a security gesture to give the impression that he is adding value.
Note: I also own a venerable ipad air2 (2009) that I bought second hand long ago to serve as a midi controller. Still a very nice, well build machine. It's not allowed to connect to wifi or it would figure out what year it is. I call it "hibernatus" (reference to https://en.wikipedia.org/wiki/Hibernatus) :)
There is absolutely no reason to release a new major version of your OS every year, and there is no reason to arbitrarily drop support for older devices (except extremely contrived ones, that I'm sure will be posted below). I made the mistake of acquiring an Ipad once. Its only job was playing YouTube videos in bed (yes I know), until Apple and Google in unison decided that it should be thrown into a landfill, because its OS was unsupported and the YouTube app, for no reason at all, would no longer work. Was the device suddenly unable to decode H.264 video or playing audio? Nope. But please just throw it in the trash and buy a new one - what are you, poor?!