Yes I agree, however on a properly managed sustainable pasture, the cows do not poop on average any more nutrients than what was eaten where the plants they ate grew. It's literally a balance. Adding a couple pounds of cow manure to an indoor grow in a 15 gallon pot is another story. How many square feet in pasture area does a cow eat to produce 2 pounds of manure? Yeah, hence we need to be careful with it!Manures in general are best from a grazer.
We often forget once upon a time these animals were. And still are an important source of organic matter and diversity.
And also be aware that much manure comes from feed lots (beef indoors) that don't represent pasture grass conversion, but instead feed containing additives that include more sodium and other mineral supplements that are excreted, even if designated "organic". No company I know of creates manure by collecting paddy's in a pasture in North America (unless you did it yourself).