I've considered hard-coding some addresses into firmware as a fallback for a DNS outtage (which is more likely than not just misconfigured local DNS.) Events like this help justify this approach to the unconcerned.
The global and distributed system relies on the system actually returning valid responses. If the root servers are broken, whether it's a problem with RRSIG records or A records, the TLD is broken.
If my domains' DNS servers start pointing at localhost, that doesn't mean DNS is a broken protocol.