Rust started with a CoC - in fact, its founder states that it wouldn't have been started without one. When starting a project, you're not just starting writing

Rust started with a CoC - in fact, its founder states that it wouldn't have been started without one. When starting a project, you're not just starting writing a bunch of code. You're potentially starting an entire community, and in time an entire ecosystem. You can't pretend that you're just writing code and ignore the people developing and using it. Simply taking the default stance ("liberty is paramount, over and above people's protection from harassment and discrimination") is not apolitical, here or anywhere else. Most people would not like to found a community that winds up going against their ethics on hugely important things related to the community and project itself. If you were an ethical vegan, you'd be unlikely to start a forum for steak-eaters - and if you're ethically pro-social-justice, you're unlikely to start a community based on unrestricted free speech within that community. To do anything else is to explicitly and intentionally support what you believe to be unethical, which is inherently unethical in itself.