They say the closer robots get to resembling humans, the more unnerving the reaction. This proves that you can go the other direction and still creep the hell out everyone.
The cage, I suspect, is intended to allow ventilation while keeping large cinders from getting into the passenger compartment and setting your clothing or hair on fire.
The original Steam Man was his father's creation. It looked like this:
It seems as if Junior's improvements consisted of "rubbing it with Brasso." But this wasn't the only steam man. Noname took the idea, shall we say, from "Steam Man of the Prairies," by Edward Ellis. His version was a bit more porcine.