The topic is open source firmware though. There's plenty of open source drivers and many of them are based on the printers accepting standardized formats.
Many, if not most printers do not block 3rd party ink with firmware - it's the driver in windows that blocks that stuff. Many, if not most, block it with a driver in the OS.
Drivers can in essence have hotlists for additional filtering or be given access to communication with an ink chip by the firmware, but AFAIK downgrading a driver doesn't work because what has really happened is it updated the firmware.
A driver upgrade can also never be sufficient for blocking copying on a MFP printer, a standardized net print protocol as you mentioned or using open source drivers either on Linux or under WSL.