I wonder if it'd just be easier to open these up to Linux distros. Out of the 3 Chromebooks I have once they go out of support they are on a quick decline to just becoming trash because I can't do anything with them after that. At least traditional PC hardware I could just put Linux on it and have a device for years to come when the hardware actually fails.
Edit just to clarify none of my devices are supported by galliumos or as far as I know any other Linux distros