The question doesn't make any sense, because it presupposes that everybody changes behavior in a timeframe that is very short compared to the typical lifespan o

The question doesn't make any sense, because it presupposes that everybody changes behavior in a timeframe that is very short compared to the typical lifespan of the animals. But I don't think that's conceivable. The total number of chickens in the world may be tens of billions but is a fraction of the number consumed in a year, I believe. Feel free to correct me if you have some knowledge about farming.