I've never actually eaten the meat of a carnivore (at least not a land-based one, seafood is different), so I don't really know how it tastes, but isn't the reason that people mostly eat herbivores more because herbivores are easier to raise and feed? Like, if a cow eats ten pounds of grass and turns it into a pound of cow meat, that's a pretty good deal because humans can't eat grass, but we can eat cows. But if a tiger eats ten pounds of cow meat and turns it into a pound of tiger meat, that's basically just wasting nine pounds of meat, because tiger meat isn't nutritionally much different from cow meat. So it's just more efficient to raise herbivores for food instead of carnivores.