> Daedong-beob unified the various forms of taxes to a single kind: rice. This, in effect, made growing rice equivalent to growing money, encouraging even more production than strictly necessary.

This is not much of an explanation, since feudal Japan had basically the same system: https://en.wikipedia.org/wiki/Kokudaka

AIUI that was a bit different; that was _notional_ rice (the tax wasn't necessarily paid in kind).

maybe Japan's feudal lords were more corrupt, disincentivizing production. Whereas Koreans paid directly to the king