Apple is offering this feature as a convenience, not as a new breakthrough in maximum security applications. This article reads like a rebuttal to a claim that was never made in the first place.
If press reports are to be believed any law enforcement organization or anyone who knows anyone in that community can already obtain an adapter that will quickly download all memory & storage from any iphone that they can gain even brief physical possession of, with or without any unlock code.
Few if any ordinary individuals currently take any action to protect their own fingerprints, which are therefore already obtainable by anyone with access to their office, home, car, or places they frequent -- or phone that they obtain.