SMS is outdated in a similar way that email is, it's something you use to receive notifications and messages from companies etc, it's not how you talk to your friends.
Thank you email is still somehow decentralized. I’m really frightened that sooner or later, one of the GAFAM tries to replace it with its own « open » solution.
It’s really not that decentralised anymore. I don’t have anything fancy, I just use a custom domain. About every fifth site can’t send email to it.
I’ve heard that if you have your own server, it’s even worse, to the point that you need to pay for some proxy which helps you avoid such problems, and also avoid that almost everything recognise your emails as spam.
SMS is outdated in a similar way that email is, it's something you use to receive notifications and messages from companies etc, it's not how you talk to your friends.