Yeah, this demo basically formed the basis for so much of modern computing. It's something I still go back to every now and again.
This demo is a shining counterexample against the 'wrongful predictions of future tech,' most likely because these were the inventions that made 'future' tech modern. The only thing that isn't really used today is the Chorded Keyset, and that still is so cool and seems so reasonable. I mean, to properly use a Keyboard and Mouse you need three hands! Using the Chorded Keys means you can type and use a mouse at the same time!