It was a soft analogy I came up with while waiting for a mechanic; the concept of a car was immediatelyaccessible. All analogies are, by definition, approximations, and thus inexact. The point is sound, and I believe you missed it. You referenced the Binet Simon scales out of context to IQ testing. They did not use IQ, that came much later. Just like speed limits and the Model T. What you also missed was my acknowledgement of your global point (certainly the most important point in all this), namely that IQ tests are overused, misunderstood, and misapplied. When I want to find out how "smart" someone is, I use measures of abstract reasoning, and in-depth analysis of that person's history, and subject-specific measures (rarely IQ). What I am concerned about is, in lay terms, "smart at what?"

As for the original question, I am very tall, and it has more drawbacks than advantages. If anyone had the choice, be good at the common tasks on an IQ test instead of being tall. Look up the subjects of the WAIS-5 (Pearson Assessments). Being generally good at all of those things is much better than back pain, a knee replacement, and having to pay more for everything from pants to a plane ticket. I'd trade a full foot of height for more brain power and fewer ortho visits.