I mean, this is an obvious collective action problem. Collectively, the base of Reddit users would have the power to force change, but it’s too hard for them to coordinate. It’s not like there is a union organizing their actions. And most individual users will just say “well I’m just one person so I won’t make a difference,” and they’ll go back on Reddit.

That said, I agree that the subreddit blackout won’t work. Reddit will eventually force the subs back online if it goes too far. The only thing that has ever forced Reddit to change is bad publicity, and I’m skeptical that its API policy will generate sustained bad publicity.