According to my understanding, the instances to be listed at join-lemmy are collected with a crawler. The crawler seems to have had problems, and this makes me curious. I am not suspecting anything like my instance not being fit for being listed there.
There is currently a TLS certificate problem on Github, once that is fixed join-lemmy.org should be updated automatically with sopuli and other missing instances.
Yes its a bug in the crawler, it throws an error about too many files. The problem seems to be due to recursion, because there are up to 2700 concurrent active tasks. Need to find a way to optimize this.