Because everyone in feudal Japan was either a samurai or ninja and all the women were geishas.

Are you serious?

Feudal Japan was a warrior society. Sure men and woman had multiple roles but at the end of the day every farmer or smith was trained to be a warrior and every woman was trained to be an entertainer. It's no different than sparta in that respect.

That's just bull. Feudal Japan was no different from the middle ages in europe. A farmer's pitchfork in your hand doesn't make you a warrior, even less a samurai. The actual amount of military, not counting farmers was less than 10% of the population.

Ninjas were never common. They were about as numerous as mercenaries, hitmen and spies today. Which means not common at all. So as a Ninja in feudal Japan you will certainly not stumble about other Ninjas all the time. There were Ninja clans but that isn't anything different from what we already have in every AC game.

To say that an AC game in Japan would be boring because there were too many assassins is ludicrous.

Any new Assassins Creed games feels over familiar at this stage.

I've been thinking "Oh, have I played this ?" each and every time I tried to play an Assassin's Creed game since AC II.

Like there hasn't been a single big budget game set in feudal japan since forever.

They could totally make it own. It doesn't have to be confined to cliche's which what it sounds like they're refering to.

Sure, because the American war for Independence is something really unfamiliar that no one, expect a couple historians know off. Ubisoft, what in the actual fuck is going on?

Japan would be great. A different culture compared to any of the previous settings, an interesting period and the presence of a faction of assassins would be more natural than ever before, without having to stretch too much.
Ubisoft seems to have this thing where they like to push their frenchness into everything as much as possible. Recently they have picked settings and cultures where the French language plays some kind of a role. Naturally, this culminates in Unity, which is set in - whaddya know - France itself.
While there's nothing wrong with that per se, it's getting a little restrictive in terms of eras and settings. Okay guys, you're proud of your frenchness, I get that, now let's go to Japan. Please.

Assassin's Creed set in feudal Japan would have NINJA!

Yeah right, you would put in both the American & French revolutions, but not during Feudal Japan. It's so fadcinating to see Ubisoft stumble.