Since we don't have the video file in front of us, we can hypothesize three likely scenarios for what archivemosaicmidv907mp4 actually contains based on the filename structure.
Search for "MIDV" or "907" inside the binary:
strings "archivemosaicmidv907mp4 2021" | grep -i midv
Archives often contain sensitive footage—law enforcement body cams, interviews with whistleblowers, or sensitive historical documents.