I haven't used Signal in a while, so I probably misremember some of what it supported. I just looked it up though and Signal's delete feature seems to leave a "This message was deleted" placeholder like what Facebook Messenger does, which looks a bit annoying to me (https://support.signal.org/hc/en-us/articles/360050426432-De...). Telegram just directly removes the message for everyone.

But with the benefit that it prevents situations where responses to the deleted message appear to have a completely different context and meaning.

the "message was deleted" can also be deleted, leaving nothing. :)