The hope is to create a new C API which doesn't expose CPython interpreter details, is easily exposed by interpreters other than CPython, and then port C-based APIs to it. Sadly it seems they aren't making much progress in 2020/2021. And I don't think it will eliminate Cython/Numpy overhead entirely, so Cython adding Numpy-specific features will still improve performance.
Also Pypy now has a compatibility shim for CPython extension modules. But last time I checked, it was slower than CPython for running one of my Numpy-based programs (corrscope), due to interfacing overhead.
The hope is to create a new C API which doesn't expose CPython interpreter details, is easily exposed by interpreters other than CPython, and then port C-based APIs to it. Sadly it seems they aren't making much progress in 2020/2021. And I don't think it will eliminate Cython/Numpy overhead entirely, so Cython adding Numpy-specific features will still improve performance.
Also Pypy now has a compatibility shim for CPython extension modules. But last time I checked, it was slower than CPython for running one of my Numpy-based programs (corrscope), due to interfacing overhead.