I think that would not be appropriate to show other people's children, but I don't think your reaction as a kid was normal, either. My ag class in middle school came out to our place to watch our steer being butchered and our local butcher was awesome, talking us through the entire process, including what he looks for as a sign of unhealthy meat. (The worst part was that our horse got pretty worked up when he shot the steer--they were buds.) All of our parents knew about the class trip and had given permission and we lived in a farming community. I grew up going deer hunting so the sight of a gutting and cleaning an animal is really not upsetting to me. If the context had been showing some of the animal farms where animals are very poorly cared for and was playing up the squalid living conditions, I would be more upset. I probably would have thought it was pretty cool when I was in second grade, too. But yeah, I would not call that a "dealbreaker," but I would probably not have wanted my 3-year-old to watch that, either, and would just talk to the caregiver about that.
(Oh, and your addition at the end made me smile--I know a lot of people who tell me they love meat but could never eat something they once looked in the eye! That is pretty normal!) =)
Oh, and I also agree with some others--that is not an appropriate show for young children anyway, and that would be more distressing than the butchering to me.