I have noted that when using Tools -> Depth compositing the resultant JPG has nearly all EXIF data omitted (no camera model, no lens info, etc.) The only remaining data is the programme name (DPP), the pixel counts (dimensions, width and height), the vertical/horizontal resolution rate, the bit depth, the resolution unit and the colour representation. No camera data.
I could (of course) put this info back in with exiftool.
I could (of course) modify the camera data on old JPGs (taken with...