Similar to how you won't convince people to consume less fossil fuels because of climate change (because people couldn't care less about some far-away problem like climate change), you won't convince people of eating less meat to reduce the suffering of the animals either.

For renewable energy, people started mass-adopting it because solar energy simply got cheaper than fossil fuels and people are greedy and try to minimize their own cost of energy, which drives them to solar power.

The same is also true for meat consumption. Saying that meat production emits lots of CO2 is not going to change mass behavior. You need to focus on the health impacts of eating meat on the individual instead.

Eating lots of meat (especially red and heavily processed meat) is known to have disadvantageous health effects on the human who eats it. Among other problems, it causes high blood pressure which are directly causing cardiovascular health problems. That's why people have a personal incentive for their own good to eat less meat.