Yes and no.

Main problem of C optimization, C is not expressive language, and using it tends to quantize problem to tiny chunks, so lost overall picture.

So yes, probably LLVM approach with optimizing already coded something similar to bytecode, could got some speedup, but with using higher level languages, speedup could be magnitudes better.

I think, future belongs to some hybrid approaches, good known domains create, or better word - handcraft with C or even on Assembly, but for less known use something like Prolog solver.