Amen.
Btw on android it's easy to make contacts self maintained. And to use an open source messenger so texts dont go through Google's servers. Not same level you're describing, but a huge defense against these "social graph intrusions."
Both of you will be carrying microphones, walking past people who are carrying microphones, and being video recorded from every building and from the networked doorstops of family homes.
And if you think that handful of megabytes is too much, they could extract a million other signals that tell them this, such as who you have pinned in the relevant apps.