You can't just stick seeds in a field if you lack water or your soil is already dead from overfarming. These are issues we face already, and they are only getting worse.

The water shortages are going to be our first impasse, because there's no remedy. Current farming uses vast amounts of water, much of which leaves the area due to evaporation. This leads to rapid desertification of regions, and then traditional farming becomes absolutely impossible (without lengthy restoration beforehand).

Reducing meat consumption definitely makes the problems less immediate, but so far it doesn't seem like we will be able to reduce that consumption. So I wouldn't count this as any near term solution.