To me, 2 things are clear:

1. It's in individual's self interest to extract the maximum economic value from the land that they control, which usually means drastically changing it from the natural state.

2. It's in everyone's best interest that we preserve a large fraction of each biome to prevent partial or total collapse of the earth's ecosystems.

How this is best fixed depends on how you think government and society should solve problems, but simply approaching it from "here's the problem, what does the end goal look like" point of view shows that something radical needs to be done.

And yes, I would include turning large amounts of farmland, even high yielding farmland, back into natural habitat.