Did you know that horses need to eat … a lot? How about rest regularly?
The way people write them in fantasy (and other genres), is they are as interchangeable and functional as cars. They are not.
Judith Tarr touches on this subject in “The SFF Equine: Troublesome Tropes About Horses” for the tor.com blog. Ms. Tarr is a regular contributor to the tor.com blog and her subjects often circle back to horses.
This particular entry busts authors for treating horses like motorcycles, dogs, and “dumb animals”. Again the link is: https://www.tor.com/2017/02/20/the-sff-equine-troublesome-tropes-about-horses/. And click on the author’s name on the article to be taken to other horse blogs she has written.