What has caused the decline of boxing in South Korea?

There was a time when South Korea had even surpassed Japan and the Philippines and Thailand in the number of regional ( Orient-Pacific ) and world boxing champions and rated fighters especially in the IBF. Since Kim Ki Soo gave South Korea its first world boxing championship beating no less than Nino Benvenuti in the mid 60s, the country has produced many elite fighters including Hall of Famer Chang Jung Koo and another HOF-bound flyweight great Myung Muh Woo. We don't hear much from South Korea as far as pro boxing is concerned the last several years now. What happened?