They could win a lot more by being smarter. Their tactics are terrible. A lot of crime could be (and is) de-escalated without the police there. They can be better trained and informed to deal with different scenarios without pulling their weapon, shouting commands, etc. They can have a better relationship in their communities. There's a lot of evidence that alternative methods result in less harm.
The "protocol" for police is also dictated by their unions and the way laws around police use of force are interpreted. In general they know they are safe if they simply kill a person as soon as they perceive a threat. They will be legally covered and physically out of harm's way. This therefore incentivizes them to use lethal force, because they have no incentive not to use lethal force.
Yes, police have a hard job. But it could be a lot less hard (for them) if laws and policies are reformed.
Crazy that this is being downvoted. The cops were responding to a call about a armed gunman actively killing. If they respond slowly or tepidly and people die, then they get yelled at. If they respond quickly and decisevly and they have been lied to, they get yelled at. They are not omnipotent.
It’s a really hard job where you have to walk the correct route through a protocol in an emergency, often while being in danger yourself