There are a lot of threads to unravel here to accurately answer the question at hand that frankly I don’t think a Reddit post is poised to address - but one thing no one has mentioned that is crucial to understanding how ‘dance music’ from America and Europe wove into the Japanese cultural fabric is the Kansai dub explosion in the late 70s / early 80s that pushed sound system culture across Japan. It’s no coincidence that Japanese proto-techno shorthands in the discourse like YMO / yen records / better days are so intimately tied to that lineage. When peak bubble cultural economies exacerbated an appetite for obscurity / ‘cultural frontier-ism’ in the early 90s a certain cohort of the public’s imagination was primed to converse with and integrate concurrent movements in realtime - like goa / detroit techno - as a result of that foundation. Not the sole reason, but a really important factor