According to the FAO Twenty-six percent of the Planet's ice-free land is used for livestock grazing and 33 percent of croplands are used for livestock feed production.
As PFL cattle are not consuming any of the 33% of the worlds land going to cattle feed, that suggests to me that, even though stocking rates are lower, when considering the pasture stocking rates of industrially produced cattle, you then need to take into account the 33% of the land growing fodder crops, and that may make stocking rates lower than with PFL cattle
Emissions from cattle farming are not just methane. For industrial raised cattle there are also a very high rate of CO2 emissions, from the manufacture and use of the inorganic fertilisers, made synthetically through an energy-intensive process using natural gas and applied to both fodder crops and pasture. Then there are the emissions from the transport to take the feed to the farmer, often involving long sea journeys. Much of the forest land destroyed in South America is cleared to grow soya for cattle food.
The manure produced by intensive cattle farming is also a problem. It has to be stored until used and it is a potent producer of methane. With PFL farming the cattle are returning their dung back to the ground, where it is quickly colonised by bacteria and insects, broken down and returned to the soil as a natural fertiliser.
