Note that in Finland we don't have the Swedish BankID. That is a totally different system that requires Android/iOS/Mac/Windows and doesn't even work on Linux PCs due to lack of software. In Finland we can still use bank identification using the paper system (like you said above) or the various systems that different banks have.
And in Finland you could also use the state issued electronic ID to login to state services like tax return etc. There is even linux software: https://eevertti.vrk.fi/en/linux-versions
And in Finland you can also use the sim-card based ID (mobiilivarmenne) for basically everything official business. I use it much more than I do my bank ID. Also at least OP bank offers "gateway" for those services which only have bank id to use the mobiilivarmenne through them instead of banking id.
I did not find a clear statement about this but I assume Android version is going up to 8 in the future. I also assume it will go up also with Xperia X in addition to XA2s. Did I assume correctly?
12. The Android Runtime of Xperia X is based on version 4.4.4 now. Will you update the Android support of Xperia X devices?
The Android Support of Xperia XA2 will be based on Android 8.1. We are looking into updating the Android Support of Xperia X, too, after we have released the support for the new XA2 range of devices.
Point 12 looks good but..
Since I did not find any update on Sailfish X and Salfish X 3.0 EA yet.. I hope that by the time the update finally arrives as a partial update, Android applications won't demand android 12 as a minimum for operation.
Or in the most optimistic scenario I don't see it as impossible to have a Sailfish OS native Fennec browser one day. After all it happened on Nokia N900 and that was more like a proof of concept due to RAM limitations.