Hm? Not sure which Signal you’re using. But it very much still requires a phone number to use. Usernames are not available just yet. There’s activity related to usernames in the GitHub repository, but no release yet.
They did remove the ability to send and receive SMS from their Android app. That was about last year or so.
We are in a privacy community. A privacy community with a specific website that makes recommendations on messenger apps. And yet, OP is asking for an opinion on comparisons between Signal (recommended by the guide) and Telegram (which isn’t even in the guide). Why would this be necessary if they weren’t thinking Telegram could be a private and secure messenger too? Even tho it’s not recommended on privacy guides. Draw whatever conclusions you want to fit your own world view. But just because others do so differently, doesn’t mean they’re bots. That’s a very lazy way to view the world. And that is also just my opinion. If you wanted to discuss the points of the article, I’m down. But if you’re coming in here to be reductive because you have a differing opinion, then this is all I’m going to be saying to you.