As someone who started learning to code with C++ followed by Python and then Rust, proper threading approaches weren't drilled into my head until I started work

As someone who started learning to code with C++ followed by Python and then Rust, proper threading approaches weren't drilled into my head until I started working with Rust. I agree with you that threading with message passing is a safer approach. Threading does add a level of complexity that isn't always necessary. AFAIK it's not outlined in a PEP, but my intuition is that Python was designed to be accessible and "simple". It wasn't built to be a systems programming language. So for all its faults with the GIL I don't think it should be a major point of contention. For any task it's always about choosing the right tool for the job. There is considerable effort at the moment to remove the GIL in future versions and implement better threading support. At 3.11/3.12, it has come a long way in terms of performance.