I guess one way they could do it would be to make a DDG server connected to the fediverse directly, then use federation to index the fediverse, so it can piggyback on the existing infrastructure and it doesn’t have to crawl all the servers and keep track of the network manually. Then I suppose individual instances could defederate and remove themselves from DDG searches, which wouldn’t be so bad if they really wanted to opt out.
I guess one way they could do it would be to make a DDG server connected to the fediverse directly, then use federation to index the fediverse, so it can piggyback on the existing infrastructure and it doesn’t have to crawl all the servers and keep track of the network manually. Then I suppose individual instances could defederate and remove themselves from DDG searches, which wouldn’t be so bad if they really wanted to opt out.