It’s not like you can stop people from creating the same community again. Just join the one with the most active users. It’s also not like this isn’t happening on Reddit too, the subreddits there just have slightly different names instead of the same one on a different instance.
I’ve added some alternatives to subreddits but I also saw that my Lemmy communities aren’t categorized yet. Is there a way for me to do that or do you have to do that?