Why is there a lack of Japanese made MMOs in the "English-Speaking MMO Market"?
Are the Japanese really that afraid of success?

Because the South Korean government subsidizes the development of MMOs and, like us, the Japanese are mostly content to import those.

>>2
It's because the market is shared like that. Japanese make RPGs and mostly console/arcade games, and South Korea decided to do their best in the PC videogame (especially online) market window. At which they've been quite successful.