Did you ask an ai to critique? Gemini have some points that weren't addressed in the post (which I barely skimmed), here's the summary of summary of summary:
Omitted Variable Bias: Conflates development stage with state size. Developing nations have small governments and high catch-up growth; mature economies have large safety nets and slower frontier growth.
Bad Extrapolation: The power-law model predicts ~36% growth at 0% spending. In reality, 0% spending means a failed state with no property rights or rule of law.
Lacks Basic Controls: Ignores panel fixed effects, reverse causality (Wagner's Law), and bundles productive infrastructure with welfare transfers.
Omitted Variable Bias: Conflates development stage with state size. Developing nations have small governments and high catch-up growth; mature economies have large safety nets and slower frontier growth.
Bad Extrapolation: The power-law model predicts ~36% growth at 0% spending. In reality, 0% spending means a failed state with no property rights or rule of law.
Lacks Basic Controls: Ignores panel fixed effects, reverse causality (Wagner's Law), and bundles productive infrastructure with welfare transfers.