This isn't about developers, it's about Apple customers. to them iPhone = Apple, not developers
This is definitely about developers.
> "these warnings would dissuade 50 percent of users from proceeding with their purchase."
How is user activity/behavior about developers?
The headline is literally "developers revolt", and the fact that half of users would be scared of a warning would absolutely matter to developers who don't want to scare away half of their users.