Amy X Zhang ✅ is a user on octodon.social. You can follow them or interact with them if you have an account anywhere in the fediverse.
If you don't, you can sign up here.
I could see Mastadon evolving like how email has if it grows. For ex, a big company comes in to start their own Mastadon instance and/or most users flock to a few major instances with the best UIs, features, and resources for moderation and development. There may also be less risk for users in joining a stable, larger instance that most instances federate with.
