I don't think we have any proposals for language-supported tagged unions (have to do them yourself), tuples (write your own macro/struct), or pattern matching (lole).

You'll have a hard time pushing for those: C will likely never get them in those forms. At least, not for another 10-20 years, since there's no existing C compiler that implements any of those things yet.

There you highlighted what i meant by they want C dead

I like to imagine that their goal is similar, yet less ambitious: to keep C alive only for those who really need it.