>>I didn't expect to see Signal listed here.

I've put Whatsapp for broadly the same reasons. So not the Op, but my 2 cents:

I cannot listen to any discussion of "privacy" or "encryption" when the software doesn't let me create multiple anonymous accounts on computing device of my choice, and instead it insists on tying itself to my most personal device and ID at the very beginning.

I don't know if Signal does it, but Whatsapp additionally explicitly requires access to your phone contact list. At which point, the end-to-end encryption feels like sarcasm. What's left? You have my identity and you have my social graph. You can tie me to anything you want six ways to Sunday. You've asked for my most treasured things in the first 30 seconds of installation. Everything else feels like ridiculous security theater that makes my life explicitly worse (especially the lack of seamless multi-device support) for positively zero benefit for myself or any of my friends & family.

I understand broad first-principles discussion, but for me personally:

I DON'T care if my discussion with my mother in law is encrypted.

I DO care if everybody I want to chat with gets my phone number and social graph.

Quite often you want to communicate with the person on the other end without disclosing your identity.

Communication platform that enforces "KYC"-like disclosure to the platform itself is misleading their users about security.

In a lot of countries your phone number is tied to your passport.