Why isn't there a universal + standard VoIP/data SMS-like message protocol?
I find it surprising how the stickiness of most of Meta's products revolve around the idea that, in essence, there is no equivalent "SMS" (provided by all telephony / telecommunications data plans) but over data rather than SMS? I.e., you use IG messenger or WhatsApp but you can't talk to users who are not on IG messenger or WhatsApp like you could just SMS someone with a regular phone.
I know there's Signal, Viber, WhatsApp etc, but all these services require you to register with the service provider rather than being able to send a data based message from User A with Telco Z to User B with Telco Y.
Has there been standards before? Any thoughts on why it hasn't emerged?
Why isn't there a universal + standard VoIP/data SMS-like message protocol?
Corporate Capture. If there were a universal protocol used by the big platforms then people could use one application to connect to each.
Has there been standards before?
This used to be a thing with MSN, ICQ, AIM, Yahoo, etc... They each had their own standard but the difference from today is those standards were open and one could connect directly to them with a stand-alone application. Pidgin, Trillian, others. It used to be people could use one application to connect everywhere thus avoiding most telemetry, advertisement, etc... That is precisely what they do not want. They want to control the flow of data and capture advertisement monetary options for all users. There are web tools today to strip telemetry and advertisement but they know most people on mobile devices will not bother to do this whereas a stand-alone application that could connect to everyone would just ignore the telemetry requests and advertisements on everything. It's also easier to force people to receive advertisements if they control the full data flow meaning if someone blocks it they can break the application flow "It appears you are using an ad-blocker" and such. With a single stand-alone tool people could choose to move to any platform easily.
What's more, with a single stand-alone application it is easier for people to properly E2EE/MLS encrypt conversations such as OTR (off the record) or other custom tools and exchange keys out-of-band making lawful intercept on the server impossible on all platforms. If people start encrypting their conversations not only is lawful intercept impossible but they can not use AI to learn what people are talking about. One simply connects to any small semi-trusted XMPP/IRC to exchange keys/identities then one need only share a fingerprint on the big platforms to boot-strap secure communications. OTR was just an example. It is in desperate need of forking and enhancements. Some big platforms claim to use E2EE but it is literally impossible for a server to manage this without having a way to inject something to perform lawful intercept. E2EE must be managed entirely by a stand-alone open source client not controlled by any of the platforms. Arguments against this are just a coping mechanism.
There is XMPP. Messengers of Google and Facebook used it in the early days. From what I know, it failed for multiple reasons.
1. The various clients and servers implemented different subsets of the functionality, which deteriorated UX.
2. Service providers have an incentive to lock you in and the average user doesn't mind. So no one pushed for it.