Is there a reason to have both of these rules in the comprehensive rulebook for Magic: the Gathering?
The referenced pair of rules fits as a first class rule in each of the two sections that it appears in. In section 400, it appears right after another rule describing how objects become new objects as a result of zone-change effects. And in section 406, it appears as a rule that is specific to the exile zone. I think it is reasonable to consider neither or both to be the "main instance" of the rule, so it makes sense for each one to not link the other.

In general, I have found that the best way to give feedback about the rules is to contact the rules manager directly on social media. The current rules manager is Eli Shiffrin, and he can be contacted on Twitter under the name @EliShffrn.