Different supported models can run the same named release and build. For example, Apple identifies iOS 27.0.1 as build 24A446, and the release supports both older and newer iPhones.
The installation package, including restore firmware packages (IPSW files) are intended for particular models or, in some cases, groups of closely related models. They are not one universal file that you can install on any iPhone. Over the air (OTA) updates download only the components required for the update.
The camera software works with the capabilities of the actual camera hardware. Apple’s camera framework requires developers to check the device’s supported capabilities before selecting formats, focus modes, exposure settings, and other features. The same operating system version therefore does not mean identical camera capabilities or behavior on every model.
So, each model gets an appropriate implementation of the same iOS release.” Apple uses a common audiovisual framework, AVFoundation, across its platforms, while camera configuration depends on the particular capture device. That combination leaves room for a change in shared camera code to affect more than one model. Hardware specific handling does not imply complete isolation between models. However, those architectural facts do not establish that a particular fix caused a particular regression.
Apple’s iOS 27.0.1 release notes identify a specific camera issue, a color artifact in photos captured at 2× under certain lighting conditions on a small number of iPhone 18 Pro and iPhone 18 Pro Max devices. That is not the same reported symptom as generally reduced clarity on an iPhone 15 Pro Max, and the release notes do not establish a connection between them.
So, is it affecting the three different cameras, .5X, 1X and 5X? If you take several photos using Apple Camera app and the same photos (exposure, composition etc.) using a third party app, do they present the same issue? There are multiple free third party apps on the Apple App Store.