Prediction is very hard, but if we're talking about centuries, I could see it happen.

There was a growing vegan trend a decade or so ago, but I think that's subsided largely because of political right-wing, conservative trends but also because people care less about ethical issues when they are struggling with basic needs and global political turmoil. If the future leans back towards the left, veganism might trend back.

Climate change might be a big factor in moving away from industrialized animal farming. it's just so inefficient. I also feel like it's becoming more popular to reduce meat consumption at least, so I could see people cutting down significantly while not adopting a vegan or vegetarian label. Dairy is a tough one though, it's much more ingrained and normalized.

People forget that we already have examples of societies like India that are largely vegetarian. If we already have a success case, I don't see why that can't be replicated globally. India fell into it through a cultural and religious accident, but I think the mindset can spread just as well in other countries, so it's important and worthwhile to keep changing peoples' minds and normalize plant-based lives.