Sucks to be them. How is that different to any other profession where things changed with new technology or market trends?

Most people working in most offices in 1980 didn't have to use PCs either. In 1990 most of them suddenly did.

We're talking about dash cams here, not body cams. They had TV shows in the 90s based on police chase videos from dash cams. World's Wildest Police Videos first aired in 97, though I suspect there were shows prior to that, the names I cannot recall. So police dash cams have been in the popular culture for almost 20 years. I think cops in Chicago (or any city) knew what they were signing up for at this point.

Tough shit. They either abused their power or stood by while their colleagues abused their powers.

When did most cops become cops? Shortly after discharging from the military. Amped up on PTSD and adrenaline addiction. Yeah, I want a camera on them every second of the day, whether they are on duty or off duty. The mentally ill should not have guns. We've had a steady drum beat that "common sense gun control" should include a psychological test. I don't think most cops coming into the job straight out of the military would be able to pass the same test proposed for civilians.