I was travelling a few years ago, and hanging out in the hotel bar in Portland, Maine, and I listened in on a heated conversation between some guy and a lady whose husband is a cop. They were discussing police brutality and the protests at the time (Baltimore maybe?), and the lady's point was basically "do whatever you want with regulating police behaviour, but I will take my husband coming home at the end of the night over anything else"
It's possible with the falling rates of crime, this may just solve itself (though increasing police training and standards is a good thing regardless).
But the state of the police and its militarization is due to policies of the last decade, meaning that deescalation wasn't tried at all. The former terrorism has become domestic terrorism, something early critics predicted (wasn't even hard). The loudest voices we hear from seem to not be able to hold a thought, because the other side needs to be silenced first.
Ultimately I believe many cops will quit due to lacking support of their governors or president. But I doubt we will see significant changes. Private security will become an even more booming market. Police departments will lack funding but will be sold expensive riot gear.