In the context of the parent's example, Rust doesn't include null at all, it just has a standard Option type with a None variant. While the other mentioned languages (JS and Go) do have null, they don't necessarily need to remove it to start getting the benefits, they just need to provide standardized alternatives and get the community to follow along (and if, say, a fancy new ? operator only worked on these new types and didn't work on null in general, that would be a strong carrot).