"The important point is that horses were NOT legislated out of...

"The important point is that horses were NOT legislated out of existence, but rather replaced by something BETTER."

Not strictly true @TechWreck. The equine industry strongly resisted the introduction of the motor car. Saddle makers, farriers, dung collectors, and especially breeders, were particularly noisy opponents. Many jobs were lost.

The industry advertised the dangers of the horseless carriages.
Motor spirit was required to be sold in glass jars from chemist shops.
Governments required a man to walk in front of the early cars, carrying a red warning flag.
The maximum speed was limited to 3 mph.
The sounding of a horn and the banging of a gong was required whenever a motor car was turning off the current road.
The use of horses on public roads increasingly restricted through government action.