The long thread of speculation has been removed because it detracts from providing accurate information and we don't have time to deal with it case-by-case. People are using tools to view metadata which group together EXIF metadata with the metadata from their computer's filesystem and the ICC profile. The filesystem metadata is from your computer's filesystem and isn't part of the file. None of the metadata is being spoofed but rather all EXIF metadata aside from orientation is removed, since orientation is used to render the image in the correct orientation when it's rotated or flipped from how the camera sensor captured it at a low level. Color profile is used to correctly render the color and is a standard Pixel color profile, not specific to individual devices or even device models. The color profile is included as an ICC profile, not EXIF metadata. Our documentation on this is correct about what's removed and. It tries to avoid giving the impression that it hides which kind of device was used to capture the photo because that involves the captured data too.
Removing orientation metadata would result in the photo being displayed incorrectly. It would be possible to create a new rotated and/or flipped JPEG to avoid needing the orientation field, but it would lower the quality of the image for no particular reason. The metadata exists in the first place to avoid needing to process the JPEG into another one in order to rotate or flip it. If it was a lossless format, there wouldn't be a need for the orientation metadata. Processing the image to remove the orientation metadata would not enhance privacy.
It would be possible to add a feature for removing ICC profile data, but it would be a separate toggle since it will impact how the image gets rendered. It will still be possible to determine the images were captured on a given type of device such as a Pixel. That can be determined based on the image content processed by HDR+. Samsung and other OEMs have their own algorithms merging multiple captured frames together, and they create unique output. It can be determined a photo came from a Galaxy phone, Pixel, iPhone, etc. based on the image content alone including after being passed through a screenshot. It would be harder to do this for more generic phones simply using a Qualcomm image processing algorithm, but Apple/Google/Samsung have very unique image processing. It's not a goal of this feature to hide that the images were taken with a Pixel, but which is not really possible. It could be made a lot harder by using RAW and processing the result in some way but then it will be specific to GrapheneOS Camera instead of generic. We had no plan to provide a toggle for removing the ICC profile, but it could be added to the roadmap if people want it. This cannot be enabled by default since it will impact image rendering and essentially reduce quality.
Our documentation doesn't give the impression that it removes more than EXIF metadata or that removing metadata can hide which type of device is used to capture the image. The app itself is clear that the setting only applies to images since the videos don't have EXIF metadata. Providing a similar toggle for video metadata is planned.