As I said, land use issues where you replace forest with cows is a problem (though not in the US, it is a problem in the developing world).
1% of US cows are grass-finished, the rest eat grain.
These grain-eating cows may be located in a place that has grass, couldn't be forest, and couldn't be agricultural land. And yet they eat grain nonetheless, from another place, that could be agricultural land, forest or otherwise nature that creates biodiversity.
The grain comes from somewhere. That creates land use issues. Not because of replacing forest with cows, but because 99% of cows sold in US stores are eating grain which must come from somewhere that is obviously not only useable for growing just grass.
Yes, in theory it's possible to have cows eat grass only, that's quite obvious. But if you were to limit beef in US stores to only those type of situations, you'd have to reduce the supply by 99% today and radically shift the way beef is produced worldwide.
And even that 1% / 99% isn't the entire story. That only tells you what is grass-finished vs cows that eat grain. An even smaller portion of that 1% are cows that are eating grass from a place that could solely grow grass and could not be used for other purposes such as forest.
Arguably that's a value judgement not everyone shares. For example, if you placed value on the carbon storage capacity and biodiversity contribution of the Forrest then replacing it with cows may not be an increase in efficiency of useful use of the land.
Arguably broad acre farming is currently getting a free ride on a number of external costs, if the math of that were to change meat grown on a small footprint would be much more competitive.