What a nice summary. You write "what does feel important...is the manipulation of 3D space, coordination, and dexterity training..." and I wanted to highlight

What a nice summary. You write "what does feel important...is the manipulation of 3D space, coordination, and dexterity training..." and I wanted to highlight this versus "making machines" -- Minsky, of course, being a big proponent of machines even for no purpose at all (the delightful https://en.wikipedia.org/wiki/Useless_machine https://en.wikipedia.org/wiki/Useless_machine). My kid has always enjoyed making shapes in 3D, but not so much the machines part. For 3D manipulation and creativity, she's spent more creative time with Magformers and the magnetic Y-ball and X-ball toys you can find at museum shops, than with Legos.