You can't raise livestock for hundreds of millions of people "ethically" -whatever that means-. That's why people industrialized the process, and on most big factories there's little human intervention.

I can't picture the day where people stop eating meat. It just won't happen, not matter what arguments you present.

The best way to go is replacing it, and the perfect postulate is lab meat, which I hope, is going to be massively produced at low cost in the next ten years. And even if it doesn't ill people, tastes the same as natural meat, you will find resistence.

So, to summarise: lab meat at lower cost than natural meat, demands plunge, billions of animals are saved every year.