If you read the article you'd see that there are 3 possible versions of police video. #1 always exists, #2 will exist in most cases (when fully implemented) and #3 is only created upon request.
1) The raw video which is stored on DVD and available for any court proceedings. This version is not altered in any way.
2) The over-redacted version which this post is about. This version is intentionally altered to try and remove any identifying features from the subjects, including suspects and also filters out videos involving specific crimes (rape or involving kids). This video is not used for any legal proceedings; it's primary purpose is to allow interested parties to review police interactions with the public.
3) Videos legally requested under disclosure laws. These are manually redacted to remove the minimum required by law to protect peoples privacy. Depending on the subjects this would generally look like the videos you see on COPS where the subjects are clearly visible but some bystanders are blurred.
The idea is that by providing the second type of videos they can reduce FOIA or similar legal requests because in most cases seeing exactly who was involved is much less important as seeing what was done to and by each person involved in the incident. Before the existence of the over-redacted versions every request to view police body cams resulted in the the need to create a manually redacted version and this took up to 1 hour/minute to process.