I don't think anyone can whatsapp chat. Somehow, whats app is the most reliable end-to-end encrypted messaging service today and many just don't know.
The system that depends on a good will and "trust me bro" is not secure by default, even if Meta/Facebook were the most trustworthy company in the world under the most honest legislation.
But given both the existing encryption as you mention, and Bitcode (mandatory for at least the Apple Watch for now), I think it's unfortunately pretty unlikely to happen.