I don't think it works that way. Putting information behind an NDA does not make it "forbidden information" that nobody can ever use. It means that one party (the one who signed the NDA) can't disclose it. To the extent someone either violates the NDA or the owner is sloppy and posts the information publicly, there are no restrictions on what people NOT party to the NDA can do with it.

Nintendo (and others) are free to go after those who violate NDAs, and to go after scrapers or whatnot, but they can't declare the information itself off-limits to everyone.