Eh, Japan is good at making bullshit hard games. They just move a few sliders and their normal action game because frustratingly difficult. Spam slider GO
Game will still be hard
No, that's how (most) western developers design difficulty. Increase enemy health by 3x, increase enemy damage by 2x, reduce player health by 0.75x, and you've got a whole new difficulty mode! Fuck yeah look at all dat content!
Ninja Gaiden Black, Ninja Gaiden 2, Bayonetta, Devil May Cry, Vanquish, shooting games, etc. all have proper difficulty design. They actually put effort in and adjust spawns by making you deal with higher rank / more difficult / more enemies in general instead of turning them into damage sponges and calling it a day. Some games even have entirely new enemies you'll only see playing on the highest difficulties.
I'm sure NG3 will be dumbed down for the babbies who suck at video games (gotta hit that 5mil GoW demographic), but at least Hayashi understands how to design higher difficulties.