You can MITM any HTTPS site in the world with an invalid certificate right now. Killing this CA won't change anything in that respect, so I still don't understand what you're getting at, or how killing this CA would make some sites less secure for a period.
All of the sites with legitimate Turktrust certificates would suddenly have invalid certificates. That's all I'm saying.
If you are operating under the assumption that Turktrust is head-to-tail untrustworthy and actively subverting the HTTPS/TLS PKI, then sure, that doesn't matter.
You said "no longer protected" which is what I'm trying to understand. All of those sites would suddenly have invalid certificates, sure, until they fixed it. But the interim period where they have invalid certificates is no more dangerous or insecure than the period before or after. The sites become less accessible, but they remain equally safe (or unsafe).
The CA itself wasn't demonstrably compromised. They issued intermediate CA certs, which makes them untrustworthy as someone who holds the power to issue intermediate CA certs, but doesn't necessarily undermine the trustworthiness of certificates issued through them directly (rather than through their bad intermediate certs), as their bad certs are not part of the chain of trust for end-user certs issued directly through them.
