The less meat we eat the better the planet will be. I think some of us have realized this is the case while others just love meat and can't see themselves not eating it. Even if we would all (or more of us) reduce meat consumption, it would still make a big difference. 

And it's also a matter of eating less overall. Since there's so much food (and especially processed foods) around us, at an affordable price, the temptation is to overeat. If we stopped doing this, we would hugely impact animal agriculture and reduce the impact on the planet.