The per capita Genuine Progress Indicator (GPI) of Thailand peaked in 2001

The per capita Genuine Progress Indicator (GPI) of Thailand peaked in 2001. In 2003, Thailand had an ecological deficit (i.e., Thailand's ecological footprint began to exceed its biocapacity). This is consistent with the view that a nation reaches its optimal macroeconomic scale prior to reaching its maximum sustainable scale.
Is it true or false?
Low-income countries in East Asia cannot increase their economic welfare by introducing policies that shift their uncancelled benefit (UB) curve upwards and their uncancelled cost (UC) curve downwards and to the right.