All of the traditional forms of music in Asia (including the Indian
subcontinent), though different sounding, have similarities in their
instrumentation. All of them use certain kinds of string and percussion
and wind instruments, and in certain cases the scales have distinct
similarities.
What may be "Japanese sounding" could still be very much Indian. Asian
music isn't very familiar to western ears (and has not (yet) been absorbed
into western music forms, unlike African music), so there's a tendency for
people to "stereotype" music from a certain country, you know like
Chinese/Japanese music thought of as plucked string instruments playing in
intervals of 5ths with a big gong in the background; or Indian music being
hippie meditation music. Actually, some forms of Japanese traditional music
sound almost "Celtic" in form, you probably wouldn't know it was from Japan.
But that's probably the beauty of music; I don't think one tribe or culture
specifically invented music, it's just something that happened, like
language or food. (If that was the case, then music was likely a
necessity). The bottom line is that many forms of music happen by mere
coincidence; I've heard some African and Southeast Asian music which has
elements of drum n bass.
Elson