This would be so fucking annoying, I don't use reddit day to day anymore but it's still a useful research tool when I see results from it on Google. I don't hate their search feature quite as much as some but I still don't want to use it most of the time.
This seems so dumb for them to do, I feel like having their content listed on search engines is s major advantage they have over Facebook et al.
Public Facebook posts are indexed in Google. I think public groups are too. There's just so much content (given how much larger Facebook is) that I doubt Google actually indexes every single public post.
Right; they mostly use Bing. Bing is the largest search engine that has an official API, so the majority of services that need search functionality use it, including voice assistants like Siri and Bixby, smaller search engines like DuckDuckGo, etc.
Well, that depends on how they implement the block, if its by domain or a blanket block (which would make sense, but I've seen weirder shit done online)