I think they mean, not allowing null outside, and using the None variant of Option to represent a lack of something.

Removing null completely is a good end goal, but in order to get from there to here we need to migrate trillions of lines of code (and having an option type available is necessary to even get started), and if that option type can't accommodate all the values that are valid in the language and existing codebases (which currently includes null, like it or not) then we can't even get started.