TLS encryption means absolutely nothing. The very system of using certificate authorities is flawed by design. NSA has no trouble performing MITM. Go search 'NSA FLYING PIG'.
https://www.cnet.com/tech/tech-industry/nsa-disguised-itself...
https://www.cnet.com/tech/tech-industry/nsa-disguised-itself...
After the PRISM stuff, folks got a lot more savvy with encryption. TLS has been tightened up a lot since then across many fronts (perfect forward secrecy, removing crap roots, certificate transparency, etc).
There's just no way the NSA can be MITMing any reasonable proportion of traffic. Possibly extremely targeted stuff, and sure, there's technically the possibility that Google is handing over keys, but if it was happening at any massive scale, people would now know.
That's why the fight has moved over to metadata now, which is what the three letter agencies are vacuuming up these days.
2. Even if they did, chrome has enforced certificate transparency, so a gag order on the CA/CT provider would simply result in the certificate being rejected.
As far as you and i know. Those things are not public. Helps with espionage (see Crypto AG).
Also this problem would apply to any key like gpg. Well, as long as it's not in a Hardware security module. Of course they could also seize that but at some point it becomes logistically impractical, at least for mass surveillance.