Re: There's Nothing Fundamentally Wrong With The Idea Behind RCS
"Even though, intrinsically, SMS and RCS also require you to use your phone number as your account identifier?"
Yes... RCS is a better SMS (roughly as good as BBM was for years) but if we're to replace these "legacy" methods of communication it'd be far better to replace them completely and not be tied to outmoded things like phone numbers or servers owned by one or more big corporations (there's no option for self-hosted Signal as far as I could see?)
In the meantime, for the bulk of my contacts I'll just continue to use SMS (and RCS where the recipient's device supports it) because it's there and more-or-less works for now.
Biting the hand that feeds IT
