Every once in a while, when someone asks a history question, there is a flurry of attempts to answer the question without referring to any supporting historical evidence. At best, such answers are purely speculative; at worst, they address an entirely different question. This is especially true of design-choices questions, i.e. those asking about the rationale of some given design at the time it was created, where people often instead opine on whether the design makes sense to them personally, or try to guess the rationale based on anachronistic considerations.
Take for example:
How did the IEC decide to create kibibytes? asks what rationale the IEC had to devise a new set of unit prefixes based on powers of 1024. Many answerers just wrote on whether they personally find separate set of prefixes sensible. At best disk manufacturers were blamed for the 1000/1024 confusion, without any sources given. The most authoritative answer was provided by Stephen Kitt, though ironically, in a comment.
(Meanwhile, the quite similar question Could we have avoided the whole UTF-16 fiasco? has been closed as opinion-based, even though, ironically, the answers under that one are in fact much better grounded in actual history.)
Under Why was `!` chosen for negation?, we have an answer attempt based on ‘emotional interpretation’, another (unsourced and, it seems, ahistorical) suggestion the symbol was borrowed from ‘propositional logic’, and another one that for example discounts
|based on confusion with Unix pipes, ignoring the fact that Unix and pipes weren’t invented until much later.
(I may add more examples later.)
I guess, with computing being a quasi-naturalistic/-philosophical/-empirical domain, where a ‘why don’t you try it yourself’ attitude is common, there is a tendency to assume that the answer to every question may be derived from first principles or discovered by a simple experiment. History doesn’t work that way, though. Either your claims are based on a permanent record of what happened (which you may need to interpret to one degree or another, but you still need to have), or they are unfounded: it’s that simple.
(I can sometimes begrudgingly accept personal recollections of what happened: as faulty as human memory might be, it still beats trying to re-derive history from first principles.)
Personally, I just downvote such answers on the spot (and even vote to delete them when possible), but I feel this might be not enough, given that they also tend to receive a number of sympathy/superficial upvotes as well, especially when the question ends up in Hot Network Questions.
What else can we do to have fewer answers of this kind?
!chosen for negation?' has more upvotes than downvotes...reputable-sourcestag will be strictly moderated, not allhistoryquestions in general. Discussion would remain perfectly fine in answers to non-reputable-sourcesquestions and in comments.