I was shocked when it was suggested in the P.SE Migration that many off topic questions that are hang overs from the original SO or others either get moved or deleted. But with over a million questions, do closed questions really detract from the users experience?
Lets take the famous cake question. Is it off topic for SO? Yes. Is it off topic for P.SE? Probably. But does it interfere with a users experience of the site? Not really. It would get buried under so many on topic questions for your search that it would rarely be seen.
Delete spree's like this worry me since so many links will get broken (not just from SO, but from others as well), you loose lots of history, and it doesn't benefit anybody. The question is still in the database for the 10k's, its still going to be requested, and most people can't access it. Who wins here?
So for my question: Do closed semi-ontopic questions really detract from SO? Note that this is only for SO since it has such a large batch of questions