Signal is not an anonymity tool–it is a privacy tool. It is not anonymous in any way. If you need anonymity you should use SimpleX over Tor.

Simplex is run by borderline grifters and Tor isn't a messenger.

I don't understand why this is so controversial. If you follow the news on the slightest the game right now is feds raiding journalists, taking their devices and then trying to unmask their sources. It doesn't matter what XYZ is "for", when the stakes are this high we need to be protecting people full stop.