FWIW, that event led me to suggest root server addresses should be treated as protocol elements, specified by RFC and assigned by IANA in https://www.iana.org/assignments/iana-ipv4-special-registry/iana-ipv4-special-registry.xhtml, such that the addresses _never_ change. In the event of a root server operator changing, the IP addresses that root server uses would transfer to the new operator.  That is (in today’s terms) while a root server operator is performing root service, they’d have a ROA for their AS in all 5 RIRs (since there isn’t an IANA RPKI TA) to announce the prefix containing the root server “golden” address they’re operating.  Should they no longer provide that service, the golden address moves to the new root server operator (or gets AS0 null routed if that root server identity is no longer needed).

Taking into consideration the truly ridiculously long tail of "mis-directed” queries to old root server addresses, the root servers’ addresses unique position in the context of the functioning of the DNS (and, as a result, pretty much the Internet), and the risks entailed when the addresses do change and hence the uselessness of the old address essentially forever, I figured permanently fixing the addresses was a reasonable solution. Others disagreed and it was clear to me it wasn’t worth exploring at that time. Maybe it is now. Or maybe not.

Regards,

-drc