PyPy is often a factor of 10 behind julia performance and projects like Numba, PyTorch (the PyTorch people had to build their own Python JIT compiler yikes!), etc. will always have a more restricted scope than a project like Julia because Python's very semantics make many optimizations impossible.
Here's a great talk from the author of the famous Flask library in Python: https://www.youtube.com/watch?v=qCGofLIzX6g where he discusses the fundamental problems with Python's semantics.
If you fix these problems, you will end up changing Python so fundamentaly that you'll really have a new language. Generic CPython 3._ code will certainly not be compatible with it.