A soft-robot gripper is perhaps more akin to an octopus tentacle than a human finger. Maybe the difference is that a skeleton is mainly needed to lift heavy weights against gravity, and all the soft-robot applications we've seen so far have involved light loads that an octopus could handle.

Hmm, I wonder how well soft robotics could adapt to heavier loads. Even with skeletal components, grip/lift strength is limited by how much pneumatic pressure the silicon can take before bursting.