I'm a personal and professional advocate from r passkeys, yet I must acknowledge that your criticisms and skepticism are valid. I don't see this as a flaw in the passkeys concept so much as a growing pain. It's a very different mental model, and I've seen businesses make some very poor implementation decisions based on some poor understanding of what this system aims to be. That in turn adds to a bad consumer impression, a growing body of bad examples for others to look to and replucate, and it all just compounds.
This rebuttalakes no sense to me. What you cite is about about transport encryption. App -> Server. The end of the process is that the receiver (Telegram servers) receives a decrypted (plaintext) message, just as kelsey98765431 is saying.