You're right. Maybe if they turned on and required SSL for everyone visiting www.youtube.com and added www.youtube.com to Chrome's preloaded HSTS list and somehow got everyone to use Chrome. Sadly, this probably won't happen, but DNSSEC adoption probably won't happen either. Even with DNSSEC, they could still do deep packet inspection on HTTP traffic going to YouTube IPs and initiate MITM attacks that way.
What? NO! They are messing with the DNS results from 8.8.4.4 (Google DNS)
Too early for TLS to do anything. Maybe with HSTS, but I still doubt that HSTS is any effective against state level MITM.