@katzentratschen@rysiek you probably just don't recognize it. I might be using pleroma or gnusocial to write this message and you'd get it all the same. That's the beauty of it. The best way to know what software someone's instance is running is to visit this instance. In my case you can go to https://framapiaf.org (second part of my user name) and see that I'm on Mastodon
@katzentratschen@rysiek right, that's because most of the switch happening right now is from Twitter to Mastodon. But at some point you'll chance upon someone using something else. Also I hope as people discover all the fediverse services more and more will start using stuff like peertube, pixelfed, lemmy or funkwhale