It's not a stretch to believe that people working on Signal have been offered bribes.
But it's definitely a stretch to believe that they've accepted them, or that it's worked. The protocol and the source code are public and well-reviewed (Telegram has a much less well-reviewed algorithm and does code drops on GitHub); it'd be a challenge to successfully fit a back door in Signal.
The thread that @durov was replying to was portraying being hired away from a public crypto project as a "bribe". Certainly that's a thing you could successfully do, but it also doesn't weaken Signal's encryption as long as there are still people working on it.
But it's definitely a stretch to believe that they've accepted them, or that it's worked. The protocol and the source code are public and well-reviewed (Telegram has a much less well-reviewed algorithm and does code drops on GitHub); it'd be a challenge to successfully fit a back door in Signal.
The thread that @durov was replying to was portraying being hired away from a public crypto project as a "bribe". Certainly that's a thing you could successfully do, but it also doesn't weaken Signal's encryption as long as there are still people working on it.