Here is a text APK that copies a text file or image from the assets to the shared storage (and reads the text from the text file or shows the image). This works for the text file (as it should be without READ / WRITE permissions). The image is copied (of course without WRITE permission, which is no longer available on Android 11), but the image is ONLY displayed if READ permission has been granted beforehand. Note: This should (in my opinion) be possible without READ permission.
FileTestSharedStorage_Nio.apk (5.2 MB)
I tested the APK on a Pixel 2XL (Android 11).
Btw, the same problem with AI2, (but there are also some other issues).