'Not the Cow But the How'?

Nicolette Hahn Niman is an American Environmental lawyer, who married a cattle rancher (https://www.theguardian.com/food/2021/aug/30/its-not-the-cow-its-the-how-why-a-long-time-vegetarian-became-beefs-biggest-champion). Although Niman was vegetarian for 33 years, she eventually took up cattle ranching herself. She has now become a spokesperson for 'ethical' beef production. Niman makes the point that small-scale rearing of cows, if they are allowed to graze naturally, can be relatively good for the land. She argues that a distinction has to be made between that approach and the intensive rearing of grain-fed cows. Niman even claims that rearing freely-grazing cows, can be carbon neutral. She says the approach has benefits compared with intense growing of crops on ploughed land. Niman also claims, that many of the negative health consequences of meat and dairy, are down to people eating highly-processed food. One issue was never raised in her account. This is the cow's inevitable release of methane, from its digestive tract. Methane is a much more potent 'greenhouse gas', than carbon dioxide. I wonder why she never makes reference to it?