Sure. Every modern car, Tesla or not, has been designed to maximise crumple zone utilisation at the exact speeds prescribed in standardised tests. Crash a little slower or faster and a different structural design would yield better survivability.

As for what constitutes "modern" in this context, the first FEM simulations for iterating car crumple zone designs have been run in the 1980ies.

Optimizing for the test, in a way that does not necessarily have any relevance for real-world performance, is much more of a possibility for software than it is for physical things. This is because of the fractal/chaotic nature of software: small differences can result in wildly different outcomes.

NHTSA testing has been developed over a long time, and in conjunction with studying both real-world and laboratory crashes, so I imagine they are quite realistic and representative. The one way that they equivocate the tests that I am aware of is to divide vehicles into weight classes, but this would be difficult to take advantage of.

According to this comment (https://news.ycombinator.com/item?id=18167535) it is possible. It's not that Tesla is optimising for performance in these tests, it's more that the tests look at the failure modes of internal combustion engine chassis.