I am not an expect in steganography but from common sense I am amusing that there is a way bigger risk that if you print it and save it physically like a paper wallet, it's way easier for the key to corrupt and not be able to read it back because of way too many colors and stuff on the game. Like the image can deteriorate physically (from the paper rotting over time and so on) and then the device trying to scan it will have a hard time guessing the key.

On the contrary with a classic normal QR code it's way simpler there fore easier for the device to scan it.