But with Signal you still need a smartphone (i.e: very bad for privacy); while with telegram you don't. Also, with Telegram you can protect the account with a password, so you can use a burner phone, literally once, and then forget about it.
With Telegram you have no privacy - no one uses the e2ee (secret chats). Perhaps because the desktop client doesn't support the feature, and even if it did, secret chats wouldn't sync across devices.
Wire works on every platform (you don't need a cellphone to sign up, only e-mail), and they released their server code a while ago as well, and documentations on how to set it up is work in progress, which means that in the future (actually even now, but most people don't know how to set it up :P) you won't even have to rely on their servers, you can easily self-host one.
I would love to use Signal, but I have to use Telegram. The Telegram desktop app is awesome, and it doesn't need a cellphone.