@IgorRock Please no cap. Cap I read them as yelling.
Good you talk about SMTP: are you informed about how Gmail, right now −because of getting majority of emails− is doing the law on the world of email? (eg. https://thedaily.case.edu/upcoming-gmail-changes-may-impact-email-delivery/ ).
Don't you think Meta becoming a major player in the Fedi world could push some 'security check', complexify the standard until no little project could follow, this type of things? Don't you see the dependency in case they takes it all as Gmail did?