I'm not going to defend police culture. It's toxic without a doubt. But if we're removing things they're allowed to use, what are they going to replace it with? In an ideal situation the police would always substantially outnumber the suspect and could simply pile on and each control a limb until they're handcuffed. What if it's just 2 cops and 1 really large, strong guy they have to arrest? If you're never worked in a job where you are required to physically subdue people larger than you, it's hard to imagine the stress of the situation. Pain compliance techniques like wrist locks are a big risk if you get it wrong, and becoming proficient takes years of practice. Even if you execute a common submission technique on someone, good luck getting them handcuffed after you release it.

And to your point about referee: the cop isn't a referee. They're just another fighter. And if they lose, there's no ref to stop the person from seriously hurting or killing them. Combine this with the fact that most cops are just average people with little to no hand to hand combat experience, aside from a few confidence booster sessions at the police academy.

I think cops deserve a lot of criticism. But let's make it constructive criticism. If we're going to take something out of their toolbox, let's at least clearly define realistic tools they can use.