You're missing my point. Development density doesn't preserve green space. It just puts more people in a smaller space. Protecting green spaces requires actual protections.

This graphic implies that there is a market solution to protecting green spaces. It's suggesting that NIMBYs who oppose high-density zoning are the reason for suburban wastelands. Zoning regulation should prioritize preserving green spaces and public lands, but deregulation is not the fix (as is implied).

You can sell the wood and drill for oil, maybe there is some gas or coal to burn.