I came up with what I think is a pretty good explanation when trying to explain the beehaw fiasco to a friend last night, here it is copy pastad
Think of it like cell service
You have TMobile, I have Google fi
But we can still talk because they both use 4g
But then Google fi blocked TMobile so I can't talk to you anymore
And if I want to be able to talk to people on TMobile and Google fi I would have to transfer my service to att
But also, the service is free to setup and run on your own
So instead of 3 or 4 big cell carriers there are thousands
Also, some added info:
Also, with the fediverse, when you transfer service you can take your data with you
Just like you can take your text messages and phone number with you
Fediverse meaning all the apps that work this way, like mastodon and Lemmy (at least those two one have data transfers I think)
It's kind of like I have gmail and you have protonmail but we can still send emails to each other. Conversely emails from "@nigerianprince.com" will probably get spam filtered or blocked and you may not be able to communicate with them.