Big 5 traits like extraversion are pretty conclusively genetic and meaningful. Twin studies show strong heritability, and personality studies show meaningful lifetime outcome differences (extraverts earn more, etc).
GP appears to be using the Myers-Briggs definition instead of the Big 5 definition. It's popular but has no backing like Big 5.
GP appears to be using the Myers-Briggs definition instead of the Big 5 definition. It's popular but has no backing like Big 5.