I wish Korea would do the same. I've taught in linguistics departments in Japan and Korea, and I've had many arguments over romanization policies.
What is the point of romanization? Who is it for? If it is for the benefit of non-speakers, then the pronunciation assigned to the Latin letters should be predictable based on common usage internationally. If it is for the benefit of native speakers...well, why? Japanese and Korean have perfectly good alphabets. It doesn't benefit Japanese or Koreans to transcribe their language into the Latin alphabet.
Pinyin is a different case. As I understand it, Pinyin was developed in the 1950s as a literacy aid for native Chinese speakers, so developers were free to be creative with the pronunciations of the letters.
What is the point of romanization? Who is it for? If it is for the benefit of non-speakers, then the pronunciation assigned to the Latin letters should be predictable based on common usage internationally. If it is for the benefit of native speakers...well, why? Japanese and Korean have perfectly good alphabets. It doesn't benefit Japanese or Koreans to transcribe their language into the Latin alphabet.
Pinyin is a different case. As I understand it, Pinyin was developed in the 1950s as a literacy aid for native Chinese speakers, so developers were free to be creative with the pronunciations of the letters.