@Gargron
I once described Twitter to my parents as public telegrams.
Mastodon is trying to create “social media” protocols like those underpinning phone calls, email and texts. Not just “read” but “respond.”
Today no corporations are pushing for interoperability due to paying for multiple email providers (eg, MCI mail, Compuserve, Prodigy) so employees could email folks outside the company.
Note: It would be 20+ years between SMTP (1981) and Gmail (2004).