I agree that AI is just a tool, and it excels in areas where an algorithmic approach can yield good results. A human still has to give it the goal and the parameters.

What's fascinating about AI, though, is how far we can push the algorithmic approach in the real world. Fighter pilots will say that a machine can never replace a highly-trained human pilot, and it is true that humans do some things better right now. However, AI opens up new tactics. For example, it is virtually certain that AI-controlled drone swarms will become a favored tactic in many circumstances where we currently use human pilots. We still need a human in the loop to set the goal and the parameters. However, even much of that may become automated and abstracted as humans come to rely on AI for target search and acquisition. The pace of battle will also accelerate and the electronic warfare environment will become more saturated, meaning that we will probably also have to turn over a significant amount of decision-making to semi-autonomous AI that humans do not directly control at all times.

In other words, I think that the line between dumb tool and autonomous machine is very blurry, but the trend is toward more autonomous AI combined with robotics. In the car design example you give, I think that eventually AI will be able to design a better car on its own using an algorithmic approach. Once it can test 4 million hood ornament variations, it can also model body aerodynamics, fuel efficiency, and any other trait that we tell it is desirable. A sufficiently powerful AI will be able to take those initial parameters and automate the process of optimizing them until it eventually spits out an objectively better design. Yes, a human is in the loop initially to design the experiment and provide parameters, but AI uses the output of each experiment to train itself and automate the design of the next experiment, and the next, ad infinitum. Right now we are in the very early stages of AI, and each AI experiment is discrete. We still have to check its output to make sure it is sensible and combine it with other output or tools to yield useable results. We are the mind guiding our discrete AI tools. But over a few more decades, a slow transition to more autonomy is inevitable.

A few decades ago, if you had asked which tasks an AI would NOT be able to perform well in the future, the answers almost certainly would have been human creative endeavors like writing, painting, and music. And yet, those are the very areas where AI is making incredible progress. Already, AI can draw better, write better, and compose better music than the vast, vast majority of people, and we are just at the beginning of this revolution.