I say this truly: animal meat is not a food, and you will find that people (to our surprise because of all of the marketing information about animal flesh) do not liquefy meat to blood assimilation.
Animal blood and milk is another story...definitely not as abundant and hydrating as fruit water / “blood”. And milks are just too constipating / clogging of the blood. Darn!
I’m not saying they’re completely useless; they are far inferior (especially raw animal milk) for the human vehicle.
If we will become aliens then I'm very sure you are right. The comparsion with a human being a car is cool but cars doesn't have pleasure sensations. If you ask a tiger then animal meat is food. So it can be food for humans as well. Are we just on earth to maximize seconds we live by drinking water? That's one way of looking at it. Another is to be here and enjoy life and experience all kinds of sensations and not just the same constantly. Clearly this is different for all humans what you find enjoyable. Many humans have thrived on all kinds of diets so no easy paths here. I wish there was an easy path but that would also make life boring. The world is too complex for that and humans have thrived on all diets.
There’s truth to that :D