Because Guido van Rossum just isn't very good with performance, and when others tried to contribute improvements, he started heckling their talk because he thou

Because Guido van Rossum just isn't very good with performance, and when others tried to contribute improvements, he started heckling their talk because he thought they were “condescending”: https://lwn.net/Articles/754163/ https://lwn.net/Articles/754163/ And by this time, we've come to the point where the Python extension API is as good as set in stone. Note that all of the given benchmarks are microbenchmarks; the gains in 3.11 are _much_ less pronounced on larger systems like web frameworks.