The key here is "properly utilized". Grazing can cause serious erosion in grasslands, and as someone else mentioned, clearing rainforests for grazing is absolutely not sustainable.
The book you mentioned looks like it wants to encourage people to be much more aware of their food production systems. I'm absolutely in favor of that. Buying meat or vegetables directly from farmers is great. For a lot of people, that's just not possible, for economic or logistics reasons.
A good compromise might be, eat only meat that you can source. If you're eating out and can't do that, eat plant based food.
Properly utilized, cows also make land more productive through utilization of their manure.
Also, not all ranch land is viable as farm land.
If cows are exclusively pasture-fed (not grain-fed), they can be a net good.
Have any of you that are seriously reducing your meat consumption tag this book?
I'd be curious to know your thoughts if so.