Sadly it is not really even an imperfect solution. Yes there have been a few departments who lost insurance, but it did nothing to stop the cops responsible for the bad behavior from working as cops, often at the agency who has to take over. Additionally the number of departments shut down is just a drop in the bucket of bad behavior. Lastly this can leave communities without adequate law enforcement.
I have nothing against increasing the cost of bad policing, but this does very little of anything to actually cause change.