An elephant can be like 8x bigger than either of those.
> we are adept at raising large herbivores for meat and other products.
You realize that cows contribute more to global warming than cars right? We should be scaling these productions down.
> Adding elephants to the list that contains cattle and horses is a logical step.
Do you know how the domestication process works?
Comparing cars with cow is unhelpful without the correct context. At minimum we should distinguish between meat cows raised on animal feed, milk cows, and grass cows (which in places are helping the environment to reduce overgrowth). Then we need to compare those to other diets.
Regardless, cars will always be worse per person compared to eating cows. I would stick with the domestication argument.
Elephants are large herbivores, we are adept at raising large herbivores for meat and other products. Adding elephants to the list that contains cattle and horses is a logical step.