1. I am not Japanese so I think some manga readers dont consider them 'real manga' worth checking out, even though the artists are all Japanese and the subjects are all about Japan.
2.They also don’t quite fit into some folks idea of literary graphic novels, because the subjects are often samurai or martial arts focused. This is perhaps seen, quite incorrectly, by some as macho, or military or war focused… therefore not suitable subjects for female readers or not matching with the generally progressive world view of many readers of mature graphic novels.
3. Our Japanese themed books also dont fit into mainstream superhero comics (where macho/fighting stuff is perhaps more popular), because, actually, there is surprisingly little fighting in our books and battles are shown in ways that, for mainstream superhero comics readers, seem disappointingly realistic, brief and devoid of ‘wham-bam’ violent thrills.
While I can understand that easy classification is a common shortcut, I think all of the above are narrow and mistaken. What our Japanese themed books are about is: history, culture, philosophy. Aren't those interesting topics, suitable for anyone? They are done in ways that don't exaggerate or simplify like Hollywood movies often do - instead we try to show the real events and people and places, according to what research has uncovered. There is no valid reason to think of such books on history, culture, philosophy as not suitable for female readers. It should perhaps be pointed out that most of the Japanese artists I work with are female (for no particular reason, its just turned out that way). And these books should be of interest to those who like mature graphic novels like Maus, From Hell or Persepolis, etc, which are also quite often concerned with history, culture, philosophy. Manga fans, if they have an interest in Japan, can learn quite a bit from these books which go into key aspects of Japanese culture/history and which are all drawn and partly researched by Japanese artists. Those who like the more traditional superhero books probably will be disappointed by the lack of ‘action’ in our books, yes - but they should be open to trying something different.
So, why not try them!