Twitter will no longer be used by ArenaNet to give players updates and information on emergent game issues, among many other things:
https://en-forum.guildwars2.com/topic/133439-visit-the-news-and-announcements-forum-for-official-updates-on-game-issues/
Not sure how well an AMA would work with the delay it sometimes takes to sync comments from the different fediverse instances.