Technically, the kernel doesn’t compile with pure standard C, they require strict aliasing to be disabled, so that alone doesn’t seem particularly crucial.

Not saying that standards aren’t useful, but they’re not some dividing line separating the true languages from the joke languages, they’re just a useful document that earns a language a few “good language” points, but those points can be earned other ways too.

For example, rust has pretty good versioning, so even if the devs did totall wreck the language in the next version, it’d maintain compatibility with older code just fine, which sort of invalidates your point, unless you’re worried that the devs turn malicious