True, but then no one ever assumed that it was anything else, as far as I can find out. But there has always been a popular conception of (film) photography as "honest" by the public at large. It isn't (or at least, doesn't have to be,) but eggregious manipulation was usually pretty easy to detect and roundly condemned when discovered. It seems to me that widespread use of digital manipulation has changed attitudes in general -- ordinary people don't seem to have the same assumption of veracity when they see a photograph as they used to. I wonder whether it seems this way to anyone else.
Mike