I don't think it's supposed to be impressive as much as just reassuring users who are uneducated about that kind of thing. I guarantee someone read this post and started being concerned that it had that information because they don't know how this stuff works.
EDIT: Plus, like someone pointed out below, Facebook collected a lot of data that it shouldn't and didn't declare as well.
EDIT: Plus, like someone pointed out below, Facebook collected a lot of data that it shouldn't and didn't declare as well.