The article leaves a lot open to interpretation, including what was expected of the tools... that could range from providing some beneficial hints to replacing all hiring. As you rightfully remark, having the tool rank candidates for highly specific jobs and its tech requirements would be a great achievement. But is also a big challenge, thus they probably were aiming at something more basic initially. Building models for broad categories like "manager" or "box packer" and hope they will detect soft skills or work ethics seems more achievable. Thus the additional star rating that can be used for hiring and provides some value.

Now having known limited capabilities isn't great. But those can and will be worked on. Unknown / unexpected biases wont, making finding them important.