At times it seemed the 2010s were just one long wistful gaze into the past, particularly when it came to trends in music.

Streaming services allow people to dig into the back catalogs of an artist's work in seconds, while YouTube uploads fill in any gaps. So when music icon David Bowie died in 2016, his fans' children were able to catch up on a multidecade career in one binge-heavy weekend.

Japanese musicians weren't immune from this nostalgic turn, drawing influence in particular from the 1980s and '90s. Globally, Japanese pop music didn't earn much attention from abroad. However, fans discovered and celebrated all things old and obscure about Japanese music, turning minor records from the bubble era into modern online gold.