Well a car operates in only two dimensions and has one given goal of transport from point A to B, so a car would maybe be a 5 or a 6. Keep in mind this scale is how close we are to actual human simulation. Humans brains deal with setting their own goals, dealing with conflicting information in pursuit of those goals, making trade offs, a constant influx of new information that affects variables in the decision making process, etc, all of which have yet to be adequately solved by AI. As the article points out, there are lots of mechanical/hardware complexities that further complicate the software with human robotics, and don't forget the average worker has 30-40 years of life experience (i.e. Learning) that a robot would need to somehow replicate. I'm not saying these problems won't eventually be solved, but AI tech has some tools that are really useful right now, but most people don't know how to use them. Instead of trying to skip up the ladder from step 4 to step 8, let's figure out ways to introduce step 4 to more people, and then we'll have more brains trying to solve the problems at steps 5, 6, and 7 to help us get to 8. Everyone will also make more money along the way :-)