No but they can run over other living beings or even cars : https://www.youtube.com/watch?v=9nYiV2YVLHg (In this one, I blame the driver)

https://www.youtube.com/watch?v=2ft9OXQ03qE (you can stop after the first hit because it repeats in loop) (I chose the less shocked one, some of them are terrible).

Yeah. For the purpose of behavior prediction while driving, horses can be approximated as very dull, very easily panicked humans. They have all the regular instincts (collision avoidance, fear of heights etc) that keep animals alive.

FSD is a complete alien that might try to kill itself for the most trivial and inscrutable reason like the sensor noise excited the neural network in a certain way.

Horses' behavior strongly depends on their education, training and the driver. A good one with a good driver doesn't give in to fear. You even can make a helicopter fly next to it if it is well trained. If FSD gets the perfection and you don't need to enjoy your driving it would be dull. It's like having a personal driver. What makes driving a car or a good horse (or whatever) fun is the interaction with them, the handling of your own decisions and your accuracy to carry out a manoeuvre