I've never been a fan of Japanimation, so I really can't say.I remember in the early 70's that Channel 20 in Washington DC was showing Speed Racer, Marine Boy and Kimba the White Lion as well as Ultraman. So early Anime was being marketed to kids even then in the OTL. It not hard to see other shows like Spectreman and Kamen Rider making to the US since they are just Superhero shows with Monsters.
What I not sure of is the relation of Anime and the influence of Star Wars and Star Trek
. Did Space Battleship Yamato come out in Japan before or after Star Wars? Did Star Trek influence the creators?
What about latter anime like Mobile Suit Gundam or Super dimension Fortress Macross? Did Star Trek or Star Wars influence them?
I thought it was Tom Corbet that was loosely based on Heinlein's Space Cadet?
And just because it's based on juvenile, don't think it can't have serious themes. Red Planet dealt with race relations & gun control (indirectly).