the japanese take their games very seriously and devote tremendous time to learn every frame of control of the game they play as if they are studying it. because of this, they tend to not care about flaws in the game as much and accept them as fundamental parts of the game.
american gamers tend to obsess over the flaws of a game and it makes them much more likely to be flakey with how and what they play.
that being said, the japanese are not mysteriously better than us in competitive games. they devote ABSURD hours to certain genres that makes them typically more skilled than the average american. however, if you take them out of those genres they are horrible.
It helps fuel most American's testosterone levels, which are apparently higher than any other nation on earth. All the CoD games that are fast paced and action packed, high intensity dialogue and situations, EXPLOSIONS!, all the Michael Bay/Roland Emmerich movies which have all the previously mentioned, and all the online video games as of late that have all the previously mentioned.
Supposed Testosterone-fueled American: Hrugh, yeah! ******* explosions, seeing military weapons and military men screaming orders! Huh, Rah! Driving a car through a warzone with men trying to kill the driver! Uh! UH! Seeing buildings collapse and shooting the **** out of people for not believing in the American way! *moans loudly* USA! USA! USA!!! *turns red, veiny and is getting off*"
Black Dick from American Dad? http://images2.wikia.nocookie.net/__cb20111121033946/americandad/images/c/cd/Black_Dick.png
Typical pc gamer's sig on Gamefaqs: Core i9, 32 GB ram, GT over 9000 graphic card and 500 TB hard drive.
.... total nonsense. Stereotypes have a basis to some extent, but it is mostly overdone, and judging that the opinion of an entire nation is the same as that one fool is even worse.
Besides the game was meant for the home market and other countries. I have not heard anything about different difficulty levels for the Japanese and the US Market.
There are some games which have been dumbed down later on, but that was also mostly because of the input of the Japanese Community, who later got (if they were lucky) an Update in that regard, rather than thinking ill of the abilities of other players.
In some rare cases it is also possible that the difficulty went actually up....