In light of the BBC's recent addition to Mastodon with their own top-level social.bbc domain, I think this is of particular importance for the CBC to join Mastodon. So far they are resistant, as evidenced by this statement:

"In an editor's blog, CBC News editor-in-chief Brodie Fenlon has suggested audiences follow the broadcaster on TikTok and other apps, such as Gem and CBC Listen."

The decentralized Fediverse is exactly where CBC should be, especially with this attack on Canadian journalism.