Could rust theoretically achieve better optimisation with a costum backend, that takes more advantage of the rich type system Information that LLVM?

Im not an expert by any strech, this is just a thought that came to me, if this is completely misguided point it out. Happy with ressources/articles to read up on.

I know writing an own backend would be a humongus task and even if there would ne noticable Performance gain, it may still not be worth it.