I'm not surprised this is happening. This is partly why I never permitted Google to put my photos in their Google Photos solution. My photos are _files_, with file extensions, taking up varying sizes, belonging inside of folders. Google Photos treated them as higher level items in some SaaS product, like posts on Instagram or something. If you wanted archival -- true archival -- then you shouldn't store your media in Google Photos any more than you should store it on a facebook timeline.