You don't need to join the other "versions", you can interact with the users on those other "versions" without having to be there. You don't have to think about it.

Analogies

Just like email. If I'm on hotmail.com and you are on gmail.com, we can still communicate without you having to sign up for a hotmail account.

Or our phone numbers, we don't need to be on the same provider in order to have a call.

Example

You are on mastodon and I am on a completely different software that has nothing to do with Mastodon, yet you can still see this reply, because despite their difference they decided to speak the same "language".

Keep in mind:

- "versions" = instances.
- "language" = a protocol.