Isn't Evangelion (in)famous for its use of Western religious and occult symbolism? I don't think it's more "Japan" coded than say Death Note (with Western characters) or One Piece (based loosely on Western pirate lore.)
Also, Eva is much more, for lack of a better term, adult-themed, thematically complex, and sexually weird than Pokemon, One piece, etc. This certainly would make it less universally popular as a cultural export.