Sounds more like an argument against the cameras at all, which in turn is an argument for keeping the footage public; as hard as it is to get most people to care about surveillance, hiding the recordings would only make it harder. Any remote possibility of something like this eventually is going to start with people being uncomfortable with it, and that's not going to happen if we aren't forced to confront the full implications of it.

Plus, there's the usual concerns of how easy it is to craft narratives by showing only bits and pieces of what happened. If law enforcement is going to be using this footage as evidence for arrests, it's definitely better that that people can have their lawyers review the public record for footage that might paint things in a different light. Sure, prosecutors should theoretically be required to share potentially exculpatory evidence with the defense, but there's no shortage of known instances where that didn't happen, and the system should not be set to to make the availability of information even more unbalanced than it already is