I recently wrote to the person who added that code to the binding. I want it for a different reason, but still want the ability to have the unreachable status available to OH. We have physical switches on areas of the house that when turned off, the hue bridge will report it as unreachable. I want to create a rule to then display in the ui the state of OFF. if could also be used to seek out problematic lights on the case that the state doesn’t reflect the actual state. It could be used for the purpose you presented as well.
The author said he would look at it, but it’s been about a week since I received a reply. Maybe you could email him as well. It could make it seem like something more than one person wants.