What strikes me as significant about the predictions, is, what has dictated our development is the kinds of materials we can produce, not necessarily the ideas behind what you can build from those materials. I realise the illustrations are flights of fantasy from the imagination.

However I wonder if you focus on the materials of the future you could make more accurate predictions.

For example carbon nanotubes is a material of the future (I've heard it said we could build a lift to the moon with carbon nanotubes).

Superconductivity, when we can make room temperature superconductive material, well blows the mind to think what you can make with that. Hover cars?

Wireless electricity, not strictly a material, but a game changer none the less.