I don’t think anybody have said that the prototype that will start testing the systems in abt. Q1/2018 will be fully autonomous from day one. It is a process of failing and learning in a safe environment to develop something that will eventually be put to work on bigger vessels, probably initially on ferries, coasters and short sea ships around Scandinavia and eventually the North Sea, (have I said that before?) before they are put out there where there are pirates and other “bad guys”.
I don’t think the videos I have linked to is telling the whole story, or is intended to. Those are meant for general consumption, not necessarily for mariners, engineers and professional security experts.
I also don’t think that the people, companies and intitutions who are working on this development are ignorant of the the potential dangers and pitfall, but if you stop searching for new solutions and better technology just because it is difficult we never get anywhere. What was is J.F.Kennedy said some 50 odd years ago?
PS> I wouldn’t be surprised if this vessel is going to be involved in early tests of prototype equipment for navigation and avoidance, until the purpose built test vessel gets going: https://www.ntnu.edu/oceans/gunnerus