Can it generate the same output despite environmental changes? This is not the same as adaptability; this is adaptability constrained by consistency in output. The ultimate adaptability outcome for Bitcoin is fiat. That’s not useful, so you implicitly disregard it. The ultimate adaptability in the universe is entropy. That doesn’t mean we view life as good if it immediately conforms with this outcome. I don’t think ossification vs adaptability is a useful frame in general. Principles vs pragmatism is a better framing of what I think you are trying to get at.