Not really true at all except progressive hard rock was perhaps a bit more influential on the progressive scene in 70s Japan. Stuff like Yes and Genesis didn't appear to have as much impact as Uriah Heep, Deep Purple, Black Sabbath and Led Zeppelin. Pink Floyd was also a huge influence on the scene. I'll list some stuff below that is all over the map and should keep you busy for a while. This is mostly prog or heavy prog but some progressive hard rock and I'll shy away from "fusion." Quite a few of these groups were influenced by King Crimson but not so much Yes, Genesis or ELP. But then some of these groups were really wild. Flied Egg, for example, have everything from Led Zeppelin with Heep vocals to syrupy pop to utterly mind bending Nice/ELP inspired compositions. Guitarist/Organist Shigeru Narumo was quite literally like a kind of Jimmy Page meets Keith Emerson. Too bad he also got caught up in recording at least one of the cheesiest "love" singles imaginable. Anyway ...
All 70s stuff:
Carmen Maki & Oz
Flower Travellin' Band
Far Out/Far East Family Band
Chronicle
Yonin Bayashi
Cosmos Factory
Strawberry Path/Flied Egg
Kenji
Magical Power Mako
Blues Creation
Tenjo Sajiki/J.A. Caezar
Samurai
Food Brain
Hiro Yanagida
Hideki Ishima
Love Live Life + One
Speed Glue And Shinki
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