Google's indexing is insanely quick too, I'll post a question on Reddit and I search Google and the reddit thread is there same day/minutes which is funny. False hope thinking someone else had my problem but it's me.
DDG (Bing I guess?) is pretty quick at that as well. 35 minutes later, your comment is already indexed.
Though I can't speak to their speed with Reddit, who is actively hostile to non-Google indexers.
Doesn't Google have some agreement with Reddit? They are probably hooked into some kind of firehose stream and index everything in basically real time.