I don’t want to sound overly negative here. But that idea is more a hypothetical proposal “we should do something about it” at this point. There is a working group mimi. But not even a draft or technical proposal, yet. And interoperability is hard, and they also want to come up with a solution that makes it secure, the messages confidential and maybe grant anonymous access. These problems aren’t solved at all as of today. On top you have to deal with spam, malicious servers, users, lawful interception and all kinds of things in a distributed platform. Then they need to come up with a text for the regulation. Write it, discuss and do several revisions, debate it. And there will be lobbyism against it and court cases because it cuts into the business model of large companies. Then it has to be adopted into national legislation and it will get a grace period.
So if you want to wait 'til 2029 (or so) to reply to your mom, go ahead and wait for the EU. I don’t have a crystal ball to be sure, but I highly doubt that this will happen in the next few years.
And on top, there is no guarantee that it turns out good or usable in the first place. There is a lot of lobbyism happening in the EU. Especially by big tech. They’ll find a way to make it a thing that just connects Apple, Meta and Google and exclude independant or secure services.