I think the app might be targeting an older version of Android. I'm using the following tag in my config file:
<preference name="android-minSdkVersion" value="14" />
I have been using this tag for quite some time now, so I'm not sure but maybe the build tool doesn't use this correctly?
Google says my app app, which has been using android-minSdkVersion 14 ever since it's release more that 2 years ago, targets Android SDK 23. So that is why I have to use android-minSdkVersion 23. Even when trying that, the error above occurs. So either Google is doing something wrong or PGB.
It basically came down to Google forcing me to set the targetSdkVersion to 23 or higher. Does this mean my app is now only suitable for Android 6 and higher?
<preference name="android-targetSdkVersion" value="23" />
No, the minSdkVersion is what controls the minimum required API level for your app (but does not guarantee functionality, though -- that's on you). Make sure, then, your app actually works below the targetSdkVersion, and adjust your minSdkVersion upwards as needed.