I think the point he was making is that it is effective in different environmental challenges and constraints. Not that it's optimal. So it might still be useful for building into a robot that's supposed to explore a environment(think space and planets for example). It may get relegated to academia, if we find other optimal solutions for our robots doing our boring chores though.
This argument sounds like a second cousin of the "chemicals are bad, but if it is natural it is good" argument. Just because it evolved in nature doesn't mean it's optimal, or it's the best system under massively different constraints. And who knows what evolution would have thrown up after a few more billion years.