The kid's machines are indeed impressive. We also used to spend hours building wire cars. We had a whole factory line. The younger lads did the straightening of the wires, some were good at using the smaller wire (often coloured wire or copper) to tie the pieces together. There were the designers who could bend the big piece of wire into the frame of the car you wanted. We then used empty polish tins for the wheels. Some of the cars had gears (none functional). It was pretty labour intensive but loads of fun. I realize now that this is why most of us had no low muscle tone or issues with our coordination. Your fingers needed to be nifty to make wire cars.

Didn't come up with the ideas, here's an example from 5 years ago in asia. https://www.youtube.com/watch?v=Kfhki3RkJv0 First time I saw this was about 30+ years ago in Nigeria, and have seen plenty variations.