Ninety two percent space savings
Using my script htmlvideo around the amazing ffmpeg project's binary:
Original video from my Canon G7X MKII - unplayable from the Web since the moov atom that defines the timescale, duration, display characteristics of the video, is not at the beginning of the file.
bitrate: 35115 kb/s → bitrate: 3037 kb/s, using the default Constant Rate
Factor of 23. Additionally
-crf 20 -preset veryslow -tune film might make
sense for archiving camera encoded video footage.