Better if included in Linux repo itself

Is this official Linux policy? Or is it the position of the R4L project? It seems inconsistent with what people have been saying on mailing lists that I have seen.

For example, people have been saying a lot that it doesnt matter if C changes break Rust code. But this document says:

>The usual kernel policy applies. So, by default, changes should not be introduced if they are known to break the build, including Rust.

and then goes on to describe exceptions in a way that suggests this will be tolerated only as a temporary stepping stone to the above approach being applied universally, eventually.

So which is it?