I don't know what you refer with "signal under attack" maybe I missed some news?

I was merely steelmaning the case for "telegram friendliness" among bitcoiners.
Lately I always get in touch with people in nostr via SimpleX, no one mentions telegram for DMs.

Due to the phone number requirement, I think Signal is more appropriate for IRL friends and family, where your number and identity is already doxxed. Usernames don't quite fix this.