The reason I prefer mangas and animes over american productions is that once something is done is done.
I call bullshit.
Manga and anime rarely seem to even end. And when they do they don't stay that way either.
Them you are the one bullshitting.
Samurai X ended like 20 years ago and stay that way, Saint Seiya the same (there was plan for Zeus since the begining, but it is taking a lifetime) but this have spin-off, even Dragon Ball the manga finished.
You don't get reboots and the few that get unexpected sequels are ones that story is close to not existing.