It is possible to make speed limited cars. The fact that no one does is evidence that people do not want them. The car market is very competitive, automakers do respond to what people want.

This isn't necessarily true at all. Other people in this very thread have proposed much better reasons. Some have even provided evidence that people do still buy cars that are limited (Volvos), without any apparent impact about speed.

You can't assert that the empirical absence of data supports just one possible explanation.

The empirical absence suggests speed limited cars are not a viable product. Whether its because people dont want them or some other reason is up for debate but by far the simplest reason and to me most likely answer is just that not enough people want them.