Good chunks of the world have people being indifferent to human abuse, or even cheering for it, so idk man, seems like a long road.

The destruction of capitalism. Animal bodies being commodities reinforces speciesism, imo.

People don't seem to be able to change society to protect the planet as a whole. So the odds are slim.

Removing the material reliance on cheap meat.

We refuse to take the actions required to save ourselves. Do you really think we are ever going to care about animal welfare?

If you make something too expensive to produce, few will try to produce it.

The death of all other life besides plants and humans.

Widespread knowledge of what goes on at those farms

A society changing-level popular children's book series that goes across the world with local dialect translations that gets made into a multi-trillion dollar grossing movie franchise that somehow also incorporates vegan ideals and sane animal treatment as core ideology. And then ones that fuse is lit, pumping the news cycle full of anger and terror driving them away from animal products for the next 3 decades or so.

They themselves would have to be locked in a pen and inhumanely abused, violated and violently threatened for an extended period of time.

Even then, I doubt it would work on a lot of people.