It is possible to JIT compile Python just fine. There are projects like PyPy that have been doing this for a long time [1]. The reason these alternative projects never take off is because many of Python's most used libraries are written against CPython's C API. This API is giant, and exposes all of the nitty gritty implementation details of the CPython interpreter. As a result, changing anything significant about the implementation of the interpreter means those libraries no longer work. In order to not break compatibility with the enormous amounts of packages the internals of the CPython interpreter are mostly locked in at this point with little wiggle room for large performance improvements.
The only real way out is to make Python 4 - but given the immense pain of the Python 2 -> 3 transition that seems unlikely.
The only real way out is to make Python 4 - but given the immense pain of the Python 2 -> 3 transition that seems unlikely.
[1] https://www.pypy.org