This question from 2009 is currently sitting on 8 delete votes. The question asks whether there are valid reasons not to use Boost (a C++ library), which is a subjective question, insofar as there is no "right" answer, and I realise SO is sternly against this. It's nevertheless still highly relevant to C++ programmers today, and the answers contain many useful pieces of information that ought to be weighed by any C++ programmer facing the issue.
OK, the question is subjective, but if we can't abide the smell of subjectivity on SO then could we not just migrate this valuable question and its answers to the Programmers SE site? Or preserve it some other way? Highly upvoted questions and answers that are later deemed "outside the rules" obviously still have some kind of value, and we shouldn't just let them disappear without a trace. If there is already some system in place for doing this that I'm not aware of, I'd be very relieved to hear about it.
In particular, Steve Jessop's answer to asyncwait's question is (as is so often the case) a masterpiece of sensible, balanced reasoning that expands one's perspective. With 192 upvotes, I'm not the only person who found what he had to say enlightening. If this kind of curated, relevant programming expertise is just going to be unceremoniously jettisoned... the waste of it just makes me want to scream.