That makes sense for a policy wonk enumerating potential positions and situating them between two extreme poles to find an efficacious strategy, or perhaps a gr

That makes sense for a policy wonk enumerating potential positions and situating them between two extreme poles to find an efficacious strategy, or perhaps a group looking to change opinion on a currently fringe idea. I can imagine that being a clarifying exercise. But it's sheer confusion to use that same concept as a metric for freedom of thought. Suppose that respectable opinions on encrypting messaging apps, treating dimentia, and political correctness all shifted and narrowed in the last 10 years. So what? You must still look into the details and context of each shift to have any idea whether or not speech got stifled in the process. So I don't understand how reference to a narrowing "Overton window" (or "Overton bubble") has any explanatory power wrt freedom of thought.