Comment by tssva

"2. On Android, it goes through Google Messages. I don't trust Google.

So, I replaced Messages with another SMS app that doesn't spy on me and disabled RCS. If I wanted to do rich messaging through data connection, I would use Signal or similar."

3rd party SMS apps use a Google provided API to send and receive SMS messages on an operating system provided by Google. I'm not sure how you think using a 3rd party SMS app would be protecting you if Google cared about spying on your messages.

RCS through Google Messages is end to end encrypted while SMS is not, so you haven't eliminated Google in theory spying on your messages but you have assured that your carrier, the recipients carrier and whomever controls the OS and app on the destination device can potentially spy on your messages.