proactive conservation easements/community land trust alternative

what is your opinion of an agriculture conservation easement that not only limits development but has a restriction that only farmers are allowed to own the land and that also the land has a restriction to keep it affordable? if you quit farming then you have to sell the land to another farmer or pass it down to another farmer. this way there is always farms available for farmers.

Why would you lock in what you could do with your land? Would the taxes be cheaper or would there be another upside that you haven't mentioned?