if you think about the energetic demand of growing food only to feed an animal that then will become food, rather than skipping this step and eating the original food instead.
most people don't want to eat grass or soy cake. letting cows graze, and feeding soycake (the byproduct of soybean oil production) to pigs and poultry is a conservation of resources.
your tulane link is not exactly good science. it relies on Clark (2019) which itself relies on Poore-Nemecek (2018). Poore & Nemecek built their data by combining LCA studies, a practice which is specifically discouraged by the studies themselves and the guidance on LCA studies generally. we can't really rely on those conclusions at all.
they also rely on Behrens (2017), which shares a problem with poore-nemecek, though a more nuanced one: they myopically distill data from input-output to calculate environmental impacts like water and land use and ghge. this seems reasonable at first blush, but in fact it overlooks the complexity of our agricultural systems. for instance, one of the things farmers feed cattle is cottonseed. cotton is grown for textiles, and the seed is largely waste product. feeding it to cattle is a conservation of resources, and doing so should in no way count against the land, water, and ghge statistics for cattle.
but that's not really here or there, as it turns out, because the thrust of the paper is not "these foods are bad for the environment" or "these foods are good for the environment". the actual claim made in the paper is "there is not actually sufficient data sources available to determine which foods have which impacts".
in torture, the point is to cause pain. the pain incurred by animals in agriculture is incidental. it's not the point of the practice. if there were some other options that were just as cost effective or cheaper, farmers would use them.
comparing other races to animals is what racists do. comparing women to animals is what misogynists do. their fight for their own rights isn't premised on their ability to feel pain, but the fact that they, too, are fully human.
that's all i've been arguing this whole time.