Tech cycles do occur more rapidly now, but it’s worth noting that it took over 300 years from the invention of the first economically useful steam engine to the

Tech cycles do occur more rapidly now, but it’s worth noting that it took over 300 years from the invention of the first economically useful steam engine to the obsolescence of the horse (which gained momentum right around WWI and was essentially complete by the end of WWII). About 200 years from the invention of the internal combustion engine — 180 or so from the first economically useful one. (Btw, steam engines didn’t replace horses pretty much at all. The internal combustion engine did.) As an aside, horses are still economically useful (although in extremely small numbers) other than for recreational or tourism purposes: they’re still used for logging, for instance, because they can handle rougher terrain than vehicles designed for similar use, and don’t get stuck if they run out of fuel.