Hello,
I don't know if it's an APP Inventor or Samsung issue but I just upgraded from a Galaxy A10 to an A23 and on the same app I don't see the list of Bluetooth items.
I have successfully paired the Bluetooth modules.
The app is the same but the List Picker gives me a black screen on the A23 while on the other I had the list of all known Bluetooth devices.
I saw a post ("Empty Bluetooth paired device list when using Bluetoothclient.AddressandNames") that seems to address the same subject but I don't understand the answer.
Jean-Michel