Continuing the discussion from Missing clear rules:
Apparently they were updated (see old version here) but the modified new version (archived here) still claims:
This document is CC-BY-SA. It was last updated May 31, 2013.
So this is obviously not true. I haven't checked if other details were changed or not, but in either case I think it's wrong to claim that the TOS weren't updated since 2013. The Mozilla Cooperation isn't the same entity as the Rust Foundation.