I recently learned how to plumb a little. Now I can do minor household plumbing fixes without having to hire professional help. A very useful skill indeed. I know it's a demanding activity that requires more than reading a book and knowing how to hold a wrench, so I know to stay away from the serious pipes and stick to little fixes.
Exactly - everyone should learn basic plumbing! Not the best analogy he could have used.
I think his point is just that a big hype cluster around learning plumbing would seem silly. There are a lot of useful skills in the world. Programming is one. Plumbing is another. Let's not get crazy and over-emphasize programming.