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/
We have been advocating for interoperability between platforms for years. The biggest hurdle to users switching platforms when those platforms become exploitative is the lock-in of the social graph, the fact that switching platforms means abandoning everyone you know and who knows you. The fact that large platforms are adopting ActivityPub is not only validation of the movement towards decentralized social media, but a path forward for people locked into these platforms to switch to better providers. Which in turn, puts pressure on such platforms to provide better, less exploitative services. This is a clear victory for our cause, hopefully one of many to come.
This is what Eugen Rochko the creator of Mastodon just wrote on his blog: