Yes, good summary. My prediction is that free-threading will be the default at some point because one of the corporations that usurped Python-dev wants it.

The rest of us can live with arcane threading bugs and yet another split ecosystem. As I understand it, if a single C-extension opts for the GIL, the GIL will be enabled.

Of course the invitation to experiment is meaningless. CPython is run by corporations, many excellent developers have left and people will not have any influence on the outcome.