[FooBarBizBazz]

I might believe it. The Philippines is today dominated by large plantations. One thesis of How Asia Works is that, although these plantations are a labor-efficient way to produce wealth for their owners, they are, net, less ecologically/biologically productive than smallholdings are (which are farmed by labor-intensive "gardening"). So the nearby countries, like Vietnam, that had land reform, which put land back into the hands of smallholders, were able to produce more food and provide more reliable subsistence to their people (if less measurable wealth).

I suspect this strongly depends on local culture, farming skills, and environment, however. The (admittedly not-unbiased) stories of land reform in e.g. Uganda (and the outcomes) are very different from those in Vietnam.

In a tropical place like the Philippines, however, I am more than willing to believe that unaccounted "ecosystem services" could provide a comfortable lifestyle for many people, if the environment were unharnessed from plantation cash-crop production. Largely because the carrying capacity is so high.