I wish that were true. Notice that I did not mention a stock miata or stock 911. A properly setup miata can and will outpace a modified 911 on certain tracks (not autocross). Of course, the driver is a key element, but will still happen with equal drivers.
The issue with this snarky comment is that it fails to take into account the limits of modifying cheap cars. There are cheap cars that may be modified to go faster than an expensive one without modifying the original structure (no tube chassis). But not all cheap cars can achieve that. Only a small list of "cheap" cars can do so. Such as the miata, civic, mustang, etc. In fact, the word cheap is not even the right way to address these cars because price does not define a cars performance or potential.