Sponsored by CIA, they'd provide tens of millions of USD each year to keep it running.

Encryption algorithm built by the NSA in Hawaii, later adopted by Zuckerberg at WhatsApp to track billions of people.

The story is well-known and published since years. That is the reason why even telegram is seen as more private than signal.

Don't ask me to defend either of those options, my opinion is that NOSTR is what we should all be using for private communications.