Ah gotcha, yes, indirect replies would need to be forwarded or something.
(To be honest, I'm already surprised that Mastodon scaled as far as it did. I will say, if I had seen the state of the web's architecture 20 years ago today, I probably also would have claimed that it was inherently insecure and that there was no way to get it to be secure enough to scale to billions of users, so... I don't know, maybe people will keep finding duct tape solutions to make it work, worse-is-better-style.)
(To be honest, I'm already surprised that Mastodon scaled as far as it did. I will say, if I had seen the state of the web's architecture 20 years ago today, I probably also would have claimed that it was inherently insecure and that there was no way to get it to be secure enough to scale to billions of users, so... I don't know, maybe people will keep finding duct tape solutions to make it work, worse-is-better-style.)