The methane from livestock argument is a dishonest one. They are looking at the methane emissions from the livestock in isolation, but those emissions are only a part of a larger cycle. To see this consider where the methane comes from. It is produced by bacteria in the stomach of herbivores (mainly ruminants) through the digestion of sugars and starch in plant matter. The sugar and starch on the plant matter contains carbon atoms (as well as hydrogen and oxygen). These carbon atoms come from photosynthesis, which takes CO2 and water and produces sugars and oxygen. The methane that is released into the atmosphere quickly degrades into CO2 and water through interaction with UV light (residency half life of methane ~12 years). This completes the cycle. Also to note, plant matter that isn't eaten by ruminant animals will eventually die and be broken down by invertebrates, fungi and/or soil microbes, releasing much of the stored carbon as CO2. Now that fungi have figured out how to metabolise lignin, dead trees no longer turn into coal.