That's pretty darn cynical, I think people in general want their privacy respected, regardless of power level.

Privacy comes from private. What you do in your function as a public servant is not private.

Civilians may be uncomfortable with police officers recording everything all the time.

See, for example, discussion about CCTV in England. There are many valid concerns about the amount of stuff that's recorded.

I think it's just technology adoption lag. Cruisers have had these cameras on their dashboards (dash cams) for a while now. At first with resistance but now it's saved more cops than burnt.

This is in part because cops (indeed, nearly everyone) behave better when their actions are recorded.