Re: knife wielding and police use of proportional force. Some food for thought:
From a martial arts instructor I used to train with (hopefully this video is visible to the public??):
The 21 foot rule that police are trained to be aware of:
Also: Look up Officer Tatum's breakdown of the Philadelphia police shooting on youtube. (it does include footage of the shooting so I'm not linking to it directly). Officer Tatum is was a police officer and does a great explanation of why they are trained to shoot for center mass (including risk of civilian injury from ricochet), and why tasers were not a realistic option given the particular scenario. If you can look past his Maga hat, he has some very insightful things to say.
I suggest, if you have the means and health, to do some martial art training and especially SPARING. You will quickly see how fast things happen, how much adrenaline effects your mind in the moment, and in general will give you a broader understanding of threatening situations. Police should be held to high standards. They need MORE training which requires more funding not less because in the moment you do not have time to think. You react. You react with what you've trained. But Police are not God and if someone really wants to do harm to you or others they will. Even in the face of "superior" weapons (See the videos above).