Believe it or not, inside the Honda gearbox was basically the same drive train we use now, just a smaller version of it. It has a cassette, a derailleur, a chain and chain ring and isn't anything too fancy. Thing is, we'll forever be using derailleurs, chains, chain rings, chain guides, cassettes etc simply because they are easy to destroy, cheap to build and expensive to buy. Chucking a gearbox on a bike would totally punish the sales of components.
On the Honda thing, I am led to believe that all those frames were disassembled and melted, deeming them non existent now.