Maybe that is possible in Germany. It is impossible here in Sweden.
Or in other words: of course you can have mobile bankid without a smartphone, just use a tablet computer ;)
Looks like it is possible in Sweden: https://news.ycombinator.com/item?id=47562094
Consider switching your bank to one not forcing you into American megacorps.
@fsflover: and my mobile phone provider. And my insurance. And my eletricity provider. And my housing associations customer portal. Getting doctors appointments. Mortgage. Union. National retirement savings account. Some of these may have some alternative left, but far too many you will be left out.
Well, I can buy a train ticket without it, so I could still leave.