Because Pypy wasn't even _mentioned_ in the JIT PEP (https://peps.python.org/pep-0744/), like it's the black sheep the family isn't supposed to talk about.

Because as proven multiple times, the problem isn't Python, rather CPython, and many folks keep mixing languages with implementations.

Because it is one of the most ambitious project in opensource world and very little is known about that. It is neglected by Python Contributor community for unknown reasons ( something political it seems) . It was developed as PHD Research project by really good researchers. PyPy had written python in Pure python and surpassed performance of Python written in C by 4-20x . They delivered Python with JIT and also Static RPython : which is subset of python which compiles directly to binary. I had also personally worked together with some of the lead PyPy developers on commercial projects and they are the best developers to work together with.