Is there special type of #ActivityPub status, which would have attributes of calendar event (date and time from - to), it's plain text portion would be capable of being viewed in normal #Fediverse clients, but at the same time, it would be presented as calendar, with chance for Fediverse accounts to join the event?
Joining by fav would be the easiest way, but perhaps there could be some mechanism, maintaimed by the instance hosting the event in the same way as polls, but different. Compatible ActivityPub clients would be able to show participants (joining publicly or privately would be nice... joining event may be special type of reply?)