I find it weird how any discussion about Signal will inevitably have a bunch of people piling on dismissing any criticisms of it. Believing that Signal is perfect has become like a religion at this point. Whatever people might think of Telegram is completely irrelevant when it comes to the question of whether Signal is actually a secure tool or not.
The fact that people working on Signal have direct ties to US intelligence agencies cannot be ignored. No can the fact that Signal is a centralized system based in US. These two things alone should make everybody very concerned.