@Jupiter Rowland well, I am probably in between Gargon and Mike Macgirvin, when talking about age. Anyway, I never thought Mastodon was first.
The wiki reveals even different timeline:
https://en.wikipedia.org/wiki/ActivityPub#Software_using_ActivityPubTo me, it seems, that Gargon simply was not as colossal nerd, as others, and somehow managed to create cult following of sufficient number of users, which were not really techies.
While Mastodon seems very simple and feature lacking, it is still very hard to explain to people without technical background, like journalists. And it is hard to motivate people to move from corporate platforms to alternatives.
I was thinking about need for decentralized social media since at least 2009, as I was watching the old web to slowly loose any relevance. (My Facebook account was canceled without any explanations as soon as perhaps sometimes like 2010?). I was thinking about basing it on bunch of combined RSS feeds, the publicly compatible vs. the activity stream, which is not so different from from like ActivityPub is made today, except that signing of content with public keys is more advanced concept, that what I was able to imagine.
I created first account on mastodon.social in 2018 and for two years, nothing much was happening. In 2020, I incited existence of mastodon.pirati.cz, the server of Czech Pirate Party, but I manged to get f.cz running only in 2023, year after the Twitter exodus of 2020, when most other Czech instances appeared.
The problem I have with Hubzilla is that I don't like how mentions and hashtags are handled. At least you learned, that I am aware of nomadic identity, which would make the Hubzilla status markup somehow meaningful, but without it, the context is next to useless - in most Fedi apps, not only Mastodon.
The only "breaking of ActivitPub" I am aware of is the consent based quoting.
BTW, all specs on the Internet evolved, Netscape played major role in evolution of HTTP, HTML, Javascript...