Many Europeans eat horsemeat. The French and - this I know personally - the Sicilians. They sell it in the open markets and it looks a little like liver to me. Kind of slimy.
Catania, Sicily...the first (and only) place I've ever eaten horse. Good taste, but tough. (Stationed in Sicily while in US Navy).
I had a slice of horse sashimi in Japan once. I found it unremarkable, but a little haunting.
I used to eat horsemeat sashimi all the time when I lived in Japan. It was delicious. The yakitori house I ate it at served it very cold, almost frozen, with soy and ginger. I had it once at room temperature somewhere else. Didn’t care for it that way. It was too rich. Never had it cooked.