Hmm, it seems the issue is actually with rpi-eeprom-config. Executing it without passing a parameter, should return the current configuration. However, it returns the error above.
rpi-eeprom-config is a python script. And while I am far from an expert, I would say it is executing as intended. Which then begs the question, why does Manjaro use a different rpi-eeprom-config than found here?
We use their “Latest Release” (Current production bootloader and VLI EEPROM release); not their git. When they release their next then the rpi-eeprom-config file will change to whatever it is at that time.
I used the current RPI OS image to edit my bootloader config. I don’t know what version it was, but it worked as documented. The one we use requires an image file as a parameter.
But that’s fine. I am not asking for an upgrade. I just thought my system was bugged somehow because I was getting the error. And then I was surprised there was a difference.