Sure, but that doesn't make it a subjective adjective. It just tells you something about what the person who uses the word thinks about what the word is being a

Sure, but that doesn't make it a subjective adjective. It just tells you something about what the person who uses the word thinks about what the word is being applied to. It seems weird to me to refer to wilderness as "underdeveloped", but more because if it really is a wilderness then it should be undeveloped. If someone starts building things in it but few enough that the zone can be called "underdeveloped" then it's no longer the wilderness. In any case, what the original person said was that the country was underdeveloped. If there's not even a single road or rail between it and its neighbor, I'd say that's a fair assessment.