The very short answer is that rust achieves what it does with lots of resources eaten by the compiler and with lots of constrains. C was created and got popular

The very short answer is that rust achieves what it does with lots of resources eaten by the compiler and with lots of constrains. C was created and got popular in the times when resources were cut and even the constrains the language imposed were considered high-level stuff. If you think why it didn't evolve, well it actually did and we call it c++. What c++ shows is that backward compatibility with already existing code prevents lots of optimizations that rust can afford to build in from the start.