Just like HN and Reddit refuse to interoperate. But it's okay because you can just make a user account on HN, and one on Reddit.

It's fucking annoying however to stay in touch with people. It used to be that everyone was on Twitter and that's it. Now it's AT LEAST Twitter, Threads, Bluesky, Instagram, Mastodon and a ton of other stuff and everyone is somewhere else and no one interoperates with each other.