You're - literally - on "Hacker News" complaining about the lack of a product. You were given one that you could easily fix to suit your aforementioned needs/demands and was a principal complaint against BankId but, instead, you want BankId to write the Linux app for you because... ...profits? This makes no sense; especially, when you would already have a hefty baseline of code to work with.
>They're different in that a service that takes Mobile BankID does not automatically support the desktop version, or vice versa.
Does not automatically doesn't - implicitly - mean that it's disallowed. You seem to be confusing the two concepts, here.
>Whether the API is similar after that doesn't matter.
We're - literally - talking about the API being the same because you made it a point that it was different. Either it matters or it doesn't. Pick one.
>Off the top of my head, Swish and Hemfrid only accept Mobile BankID, with no alternate authentication options. Swedbank accepts Mobile BankID or their custom OTP hardware token, but not desktop BankID.
O.k.? We're still in the swamplands of those are problems created by the app developers and not BankId, correct..? I'm not sure I'm following how the app designers' decisions are the fault of BankId...