Researchers have linked dietary data from over 55,000 individuals with data on the environmental impacts of the foods they eat. The team, from the Livestock, Environment and People (LEAP) project at the University of Oxford, found that the dietary impacts of vegans were around a third of those of high meat eaters. They also saw a 30% difference between high- and low-meat diets for most of the measures of environmental harm.
After extracting the protein and nutrients for plant-based products there’s not much nutrition left to use it as animal feed though. It’s probably not nutritionally appropriate for cows, pigs and chickens at that point. Using it for insect farming would seem more realistic to me, or as a growth medium for edible mushrooms.
when you have a ton of soy cake, I guess you can decide what to do with it.