Matrix probably by default, because most Matrix clients already support E2E out-of-the-gate (Element, Mirage, FluffyChat for iOS, Syphon for Android, KDE NeoChat, nheko). Though you could also have E2E on XMPP, it’d just require more effort to find the appropriate plugins/settings on your part, than with Matrix.
Matrix probably by default, because most Matrix clients already support E2E out-of-the-gate (Element, Mirage, FluffyChat for iOS, Syphon for Android, KDE NeoChat, nheko). Though you could also have E2E on XMPP, it’d just require more effort to find the appropriate plugins/settings on your part, than with Matrix.
That may be the case with some older clients, but the client I use has it enabled by default…