Re: the “thousands of spam/bot communities at lemmy.world?” question in your source, yeah there’s about 6k. A user tried to create about 2000, all called “serverhold” if you want a way to exclude them, got banned, and in retaliation created about 4000 with that junk string.
The admin of lemmyworld said it’ll take time to remove them, but I don’t know why (there seems to be the functionality in the API)