I’ve read in an Article that meat production causes a lot of co² emission. Now I was wondering if we stopped eating meat completely, would that be sufficient to get under the threshhold of emissions what the planet can process? What is that threshold? Where are we now? How much does meat add to this?


“Everyone will just X” when X individually makes obvious sense for most people.
For some, it’s a matter of cost. The cheaper option tends to get a lot of adopters. Making the better option cost less is sometimes a matter of engineering and innovation improving the cost of the better option. Or sometimes it’s making the worse option cost more, sometimes directly through taxation or indirectly through regulations. Electric cars are pretty much on a self sustaining path at this point, where the economics of electric cars can be a much better financial decision for themselves personally, compared to similar ICE vehicles.
For others, it’s a matter of cultural influence, where trends in adoption just make things different. Tobacco use, especially actual smoking, is way down. Drinking alcohol is down, too. In my lifetime, helmet use for bicyclists and skiers is way up. These broad societal preferential shifts can happen without necessarily having big mandates from government.
And even if nudged somewhere by temporary government policy or price, sometimes people stick with that option long term if that’s what they learn to prefer. Seat belts kinda went this way, where seat belt usage rates went way up between 1980 and 2010, so that even after federal regulations were struck down by the courts and state level enforcement dwindled in the past decade, everyone still wears seat belts (including when visiting places where they’re not required).
And of course, the big influential force for changing behavior is government policy. As a society, we’ve pretty seamlessly moved off of things that were banned (leaded fuel, CFCs), even if the transition took a few decades (lead pipes, lead paint), or quickly adopted things that were mandatory (child car seats, bike helmets).
Emissions from food production is one of those things that can shift a bit from all of these factors. We’ve shifted away from beef towards chicken in the last few decades, and that alone has made a difference in greenhouse emissions. We might see more shifting down that line, just culturally. Or we might see some economic nudges from the fact that beef and dairy production are so costly for reasons correlated to their environmental impact.
But ultimately, meat doesn’t contribute nearly as much as driving does, for the typical American household. The real impact comes from how we design our cities, not on how we eat.