I don't usual respond to conspiracist posts, but maybe you're going to take Moxie Marlinspike's word for it ?

https://signal.org/blog/whatsapp-complete/

Conspiracy theories aside, why would anyone's word be sufficient? How about the code? Give us the code, then we don't need anyone's promises. Enough with promises!

Even the code is not enough, is it? Once you have it, how do you know that's what they deploy?

I deploy my own code.