Backing up the "master archive" is critical! The "derivative" files shared out aren't so critical, as they can be reconstructed from the "master archive". An example is MPEG-2 will preserve videos at high quality, but with large file sizes.
I agree that backing up the master archive is critical, but for video that archive should be the original file created by the video capture system, preferably a non-lossy archival format such as FFV1 or HuffYUV in order to reduce or eliminate generation loss and retain all the original data and metadata for future reprocessing. MPEG-2 tosses away potentially valuable information in order to reduce file sizes and is therefore better as a publishing format than as an archival format.