Not going to dispute that. If I spend time optimising code, I might do it as well in an environment like Swift/Metal instead of Python.

Yeah, properly written Python is at extreme worst O(1000) times slower than speeding it up code with a Numpy/Numba/c/Fortran/etc. implementation. Brute-force loopy code in Python I've seen is 100x slower than the compiled alternatives. So I agree, these extreme numbers are the sign of writing the worst possible Python implementation of a thing and saying Python sucks.