I don't want to add more to your fears, but also remember that LLMs have been trained on decades worth of Python code that assumes the presence of the GIL.
I wonder if companies will start adding this to their system prompts.
Especially when they've already been force-fed with ungodly amounts of buggy threaded code that has been mistakenly advertised as bug-free simply because nobody managed to catch the problem with a fuzzer yet (and which is more likely to expose its faults in a no-GIL environment, even though it's still fundamentally broken with a GIL)?