iOS11 seems to have almost purposeful security weakenesses. I'm willing to give Apple the benefit of the doubt here, but only if they fix whatever flaws these guys and Cellebrite are using to break into iOS11 iPhones.
Both those decryption devices seem to rely on iOS11 so it must a new change, which means it shouldn't be too hard for Apple to figure out which one of its recent changes caused this weakness in security.