Why does this analogy survive?
At least once a day you'll hear something described as "the size of a Volkswagen".
This was valid briefly from about 1950 to 1970, when VWs had a constant size and shape and were distinctly smaller than most American cars. But it's useless before and after those years.
Before 1950: The basic Beetle was about 160 inches long. When it was developed in the early '30s this wasn't notably small. For instance, a 1932 Plymouth four-door sedan was 166" long, and Model Ts were only 138" long. The VW was much smaller
inside because it was low and streamlined, while the typical American car was upright and square.
After 1970: Many American cars returned to the earlier dimensions, similar to the Beetle. Now lots of them are shorter than a Beetle, and lots of cars with the VW brand are giant SUVs.
Considering the imprecision of any analogy, "About the size of a car" would do in just about all circumstances.