The technology exists to have cameras everywhere, and we should. Criminals avoid punishment because there is no evidence, especially when they are politicians or police or soldiers.
The obvious special cases are police body cams and dash cams, where some types of crime would stop of people knew they were surveiled.
The trick is to have total surveillance but also privacy.
HDMI is an existing technology where video data can only be transmitted once a secure key is provided. So video can be recorded by a box and encrypted on internal storage. It can only be decrypted and viewed if the user has a certain key.
This is perfect.
Secure encrypted video camera systems can be built cheaply, using existing technology. In general nobody will ever be able to view the recordings.
If somebody alleges a crime, the camera can be brought to court, where a judge can order the key to be found. The key will only be held by a specially elected group of officials who must all be present for the video to be viewed.
This way we can have both security and privacy.
Although it is possible HDMI could be hacked, even if this happens this system is much better than we have today. Today the surveillance is transmitted to many places and people insecurely. It can be used for many things. The recordings can even be remotely deleted after a crime is committed, which does happen sometimes.