Yes, your calls would be traveling over an encrypted tunnel to the carrier instead of the (simulated) cell tower, thus preventing the Stingray/site-simulator from carrying and listening in on your call.
However, it would not stop someone from listening to the call at any point over the rest of the path since the call itself is not encrypted, only the transport between the carrier and your phone.
"In the spirit of open source, we're working to help develop updates to the project to address some of publishers' and end users' concerns. Specifically, here are some features we're developing to address concerns that have been expressed about AMP: ... A way for end users who would prefer not to be redirected to the AMP version of content to opt out"
Indeed. We have pagespeed, use it as a higher signal.
But no, Google wants to own your content and users. Only very naive person believes they do it in order to fast up the web. If they started punishing harshly slow websites with 10mb of js, believe me ,it would change over night.
However, it would not stop someone from listening to the call at any point over the rest of the path since the call itself is not encrypted, only the transport between the carrier and your phone.