Not having a CoC is like not having an employee handbook.
In theory, we're all nice people, and nice people don't need laws or handbooks to tell them what to do or who to behave.
But we're not all nice people. And when bad things happen, you need to have something written down that you can point to and say: "Hey, you violated this thing you said you agreed to." CoCs are not preventative measures (they don't proactively reduce bad behavior), they're more helpful for throwing out community members when they do something bad.
In theory, we're all nice people, and nice people don't need laws or handbooks to tell them what to do or who to behave.
But we're not all nice people. And when bad things happen, you need to have something written down that you can point to and say: "Hey, you violated this thing you said you agreed to." CoCs are not preventative measures (they don't proactively reduce bad behavior), they're more helpful for throwing out community members when they do something bad.