What exactly do you believe that this CoC addresses by the way? I am generally unconvinced that a CoC does anything positive at all, but what is it that you believe that it does?

The way a CoC would work, I think, is hard to quantify.

Sure, it may mean that some folks rage-quit on principle, some will continue bad conduct and get themselves kicked out, some will subvert the intent of it one way or another.

But if a CoC is "successful", it will mean that gradually you'll start to see folks who were previously under-represented start to contribute. You'll see more diversity and less fear and loathing. Is that a worthy goal? Yes, for many.

"Worthy Goal" Has that worked anywhere in practice? Who is underrepresented right now and why? Do we know?

The type of diversity archived by a CoC like this is litteraly skin deep anyways and might cost you diversity of thought. We already see "wrong" think beeing excluded.

It is also suspicious to me how this change was seemingly not discussed in any way prior and that it was a very sudden change for him.