- start with the humans that pollute more - which is way more correlated to their consumption that their solar roof surface. Sorry USA, you go first. Others high standard living countries follows.
- Regarding the cows, they have a shorter lifespan and don’t shop much neither do they heat their house or shower water. We could just stop breeding new ones and keep the existant till their death.
Their farts are not a long term issue like so damn many people make it out to be. (and I don't think they don't produce (that much) more than the wildlife and plant rot they replace over the total outsized amount of space they actually take up) If there's a reason to have less it's because we chop down forests for more grazing space to grow the herd. Environment impact aside these are carbon sinks even if vastly less efficient than kelp forests or bogs or the like. Also because we use a bit of fossil fuels for fertilizers in part for their feed. That said the manure they produce is probably invaluable in avoiding famines if we're going to stop utilizing Haber–Bosch or start utilizing more expensive methods without gas.