From only a week ago here on Hacker News, a comment about a news story on Australia:
https://news.ycombinator.com/item?id=6037235
From the article:
"The contract was prompted by Telstra's undersea telecommunications joint venture called Reach. When it sought a cable licence from the US Federal Communications Commission, the DoJ and the FBI insisted on a binding security agreement.
"The contract does not authorise Telstra or law enforcement agencies to undertake surveillance. But under the deed, Telstra must preserve and 'have the ability to provide' wire and electronic communications involving any customers who make any form of communication with a point of contact in the US, as well as 'transactional data' and 'call associated data' relating to such communications."
. . . .
"The document was signed by Douglas Gration, a barrister who was then Telstra's company secretary and official liaison for law enforcement and national security agencies.
"He told the Herald he could not remember much about the agreement. 'Every country has a regime for that lawful interception,' he said. 'And Australia has got it as well.'"
This looks like a pattern of mutual agreements among governments that cooperate in routing and connecting cables for international telecommunications. The statement is NOT that every telephone call from Australia to another country is listened to, but that a data archive is maintained that might be accessible with court orders. Particularly significant is the statement that other countries ask for the same arrangement if a cable connects to or through that country.
Switching email providers has little to do with what governments have access to your data by mutual agreements among the governments.