This being the default answer for all issues kinda prevents any discussion of any issue that might be unrelated.

The API problem is that you do (ignore the ampersand issue for a moment):
curl 'https://lemmy.world/api/v3/community/list?type_=Local&sort=Old&limit=1&page=250010&show_nsfw=true' | jq .
and it will return a response for a page of Communities it can't possibly have. It's a never-ending list that can't be indexed.

The thing, it returns without issue - there's no connectivity problems that DDOS attacks would cause.