PyPy's difficulty with invoking native code is not because of its tracing JIT but because the CPython C API makes it very hard to deviate from _any_ CPython implementation details, including e.g. choice of memory management and precise layout of objects in memory. I wrote extensively about it here: https://pypy.org/posts/2018/09/inside-cpyext-why-emulating-c...

HPy proves that it is indeed possible to have high-performance C extensions with PyPy: https://pypy.org/posts/2019/12/hpy-kick-off-sprint-report-18...