So, you'd think static typing was a major win but it actually isn't (surprisingly) for a JITed language. Most of the benefits of statically typed languages comes from memory layout optimizations. However, that sort of layout optimization is something that every fast JITed language ends up doing.

This is why, for example, javascript in Graal ends up running nearly as fast as Java in the same VM. The reason it isn't just as fast is the VM has to insert constraint checks to deopt when an assumption about the type shape is violated.

https://www.graalvm.org/javascript/