We don't find these systems intelligent because, on inspection, they arent.
We are intelligent. Not "magically", but actually nevertheless.
Our intelligence, and that of dogs (, mice, etc.) consists in the ability to operate on partial models of environments; dynamically responsive to them; and to skilfully respond to changes in them.
This sort of intelligence requires the environment to physically reconstitue the animal in order to non-cognitively develop skills.
It is skillful action we are interested in; and precisely what I missing in naive rule-based models of congition.
It's why I use "AI" and "ML" interchangeably although I know it's technically incorrect - the formal definition doesn't match what people are currently thinking.
So yes, "any solution that imitates intelligent behaviour" is probably right, but with nuances with regard to what that actually means.
Edit: yeah, you can downvote this, but current AI research splits right along this line, whether it's symbolic or statistical. Some AI courses will use NNs, others will use Prolog and ASP. You can't just dismiss a whole field of research by reducing AI to statistical methods.
I know that AI researchers are usually a bit dismissive about the other area. I don't like statistics either. Reducing the whole of AI research to statistical approaches (and NNs are one of those) is disingenious and dismisses hundreds of researchers doing important work.
You may not want to have rule-based image recognition, but if your car decides to run over somebody, I feel we better have an explanation for this behaviour based on reasoning and logic.
If you just replace ML with AI everywhere in this article it is going to make sense.
The article has other problems, one being the main premise.
The problem isn't to drive a car around track (which is what the polynomials did) but rather write a program that can figure out how to drive a car without you knowing how to solve it.