How is this better than compiling everything to WebAssembly and using V8 as your interpreter?
For dynamic languages like JS you can’t actually make these optimizations AOT, which is why we JIT JS in the first place.
GraalVM improves the performance of Ruby, Python, etc and also allows you to run C and C++ code in the same VM as a bonus with good performance. Unless you're using an intermediary bytecode like WebAssembly or JVM Bytecode you will also need to ship full sources with your C or C++ application.
BTW. In my experience so far, when it comes to software - a bird in the hand is worth ten in the bush