I don't see any indication that DNSSEC would have been relevant there? Their assessment was that that interception (and certificate issuance) were completed by redirecting traffic for the legitimate IPs to another destination. The DNS records continued to work as expected.
> real world compromises of major sites that don't use DNSSEC?
Without any other changes to this infrastructure DNSSEC by itself wouldn't have prevented this, but it could have been combined with something else like a CAA record.
You're doing a jazz-hands thing here where you equate a breach in DNSSEC (which virtually nobody uses), to a new susceptibility in the ordinary DNS (which everybody uses), such that an attacker could spoof arbitrary DNS lookups to arbitrary CAs. Obviously the two things aren't comparable.
When you make arguments like this, or the weird SSH argument you're making across the thread, or the weird "this would be good for Wikileaks" thing you did elsewhere, you clarify how tenuous your argument is. Remember, you're in the position of arguing that 95%+ of large site operators are wrong about this, and have been for decades, and you're the one who's right. That can definitely happen! But it's an extraordinary claim and your evidence thus far is pretty terrible.