“For hundreds of years, the horse was the prime mover of humans”
Far longer than that plus other animals such as the camel.
He also states the automobile as the prime mover of people the last 120 years. 120 years ago was 1897. In 1897 the prime mover of people was still horses (and trains). If he’d have said 110 years I could have let it slide, even though most rural areas still were horse and buggy/wagon in 1907.