The public notion of good policing and the actual practices police departments follow have been diverging for several decades (if they ever converged). What we're seeing right now is not some inexplicable increase in bad behavior or cops deliberately targeting journalists. For modern American police this is just business as usual, except the volume of deployment is significantly higher than in the past few decades and the visibility is much higher as well.
Edit:
There is a flip side to this coin. When you have a systemic problem of this scale, you should be cautious about making simplistic (especially moral) judgements about individuals in the system. When someone's training, incentives, position in the community and even equipment nudge them towards bad actions, even decent people will routinely do bad things.
For some reason, you always have a few commenters who want dismiss shocking events by saying the shocking event is not 'surprising' or that it 'has always been happening' or was in some sense 'already known'. As if that should make it less morally outrageous. I've never understood what purpose that debate was supposed to serve.