Aye, which I think is reasonable, especially in the context of the GIL-removal approaches that were on the table at the time and the effort needed to implement

Aye, which I think is reasonable, especially in the context of the GIL-removal approaches that were on the table at the time and the effort needed to implement them in CPython. I think the PyPy folks want to get to a place where you can run PyPy in modes tuned for either single-threaded or concurrent workloads.