Earlier quoted context omitted.
Most cattle feed isn't digestible by humans, so it doesn't matter. Replacing grass with more human-edible crops would probably introduce new problems of similar scale. You might ask, can we just process the grass into something humans can eat? Well, that's what cattle are for.
Better to leave natural habitat on that land rather than clear-cutting forest for grazing land, as happens so much these days and in the past. Better food production efficiency means less forest razed which is a significant win.
Livestock are a central part of traditional agriculture and they're more or less essential for people who want to operate small-scale sustainable farms. It's a complicated issue that too many people enter with ideological presuppositions. Which is not to say current agricultural practices are necessarily perfect.