ActivityPub Conf's organization has happened from extremely limited resources, but I think at this point I think it's going to be amazing. Looking at the list of people registered and talks already submitted gives me confidence that this is going to be a heck of an event.
There's still slots open if you were thinking about registering, and talk proposals are still open until Monday! https://dustycloud.org/blog/activitypub-conf-2019/