[eqvinox]

The argument against this is the same as with the parent post to yours: UX. Signal has made the decision to use the phone number as identifier, and that's part of the reason it works so well for novices.

I totally agree with you; I would not have bound identities to phone numbers either. However, Signal is reaching a wide audience like little else has while still being more open than the other encrypted messengers. This seems to indicate that Signal has taken the best balance in compromise.

[Freak_NL]

The UX argument is simply not convincing at this point. Sure, for an MVP it seems a fair choice, but they are way past that stage of development. They could simply keep the mobile phone number as an option, and even default to it on mobile OSes, and the UX would hardly suffer.