That's exactly why. Our, now, limited beef is exported because it's insanely high quality and we import cheap crap. Beef producers in LatAm are essentially slave labor for JBS who makes extraordinary margins on selling beef to Walmart etc.
Meanwhile, we are losing (I think) 1400 ranches a year, probably more, even as cattle prices are at an all time high.
As to you other question, cattle ranching hasn't been the largest land use for decades. Might have been before 1973 when Secretary of Agriculture Earl Butts made his famous "you will farm commodity crops fence row to fence row" speech but no longer. It's all corn, soybean, wheat, etc.
It's sad.