Just re-watched The Wolverine (2013). Any Japanese redditors who can tell how accurate the depiction of Japan was?

So a friend of mine felt it was incorrect for Shingen to say "God's mistake" about mutants because it was too christian for a Japanese man (Shingen is very unlikely to be christian). I don't know if this is the case. Were there any other places where the film was very accurate or inaccurate?