The idea was to track AI-only changes and add the trailer when such changes were detected AND the setting was enabled. Obviously, we didn't want to attribute all changes to AI. There is a bug in change detection (which slipped through testing), which led to even non-AI changes being tracked. And thus we have this problem.
The PR linked here wasn't even implementing the feature, it was changing the default for the setting.
In another comment you say you caught it in testing and didn't think it needed fixing, which is it?