I've been a regular reader of this subreddit for several years now. Although I am not a historian, I recognize that there is some wiggle room in interpretation of data and historiography in general. Pretty near every single answered post I have come across (to my recollection), however, has contained either one "winning" answer (by which I mean, one person answers the question so effectively that no one else attempts OR no other answer receives any where near the same amount of upvotes) or several harmonious answers. Has there ever been a serious disagreement in answering a question on this subreddit though? If not, why do you suspect that that is? Or if it is merely uncommon to find disagreement, why?
Cordial disagreement and discussion do occur on a fairly frequent basis here - indeed, differing scholarly interpretations have been the driving forces behind some of the best discussions I've seen on /r/AskHistorians in the past. I'll leave in-depth discussion of historiography to those whose prose can do it better justice, but just as an example of a couple of disagreements in which I've been involved in the past:
In this discussion of naval aspects of the Winter War, I debated with /u/TehRuru34 about several aspects of the conflict. This was a fascinating and humbling exchange for me, as /u/TehRuru34 firstly caught me out on a mistake I had made in my own notes about the calibre of several Finnish naval gun emplacements - I had recorded the largest of them as 16 inch guns when the source I was citing stated they were 12 inch guns - and additionally because it highlighted the ongoing disagreements in more scholarly accounts of the conflict. As I discuss in my edit of the original post, the book from which I drew my discussion of the Soviet battleship Marat and cruiser Kirov clashes with the sources /u/Tehruru34 presented. Trotter, in Frozen Hell, claimed that Marat had been damaged in an engagement with Finnish coastal artillery in the early days of the conflict, while Soviet primary records indicate the ship resumed active operations so soon after the engagement that it clearly had not required repairs.
In hindsight, this was an exchange that really highlighted for me the deeply flawed nature of English-language historical accounts of the Winter War, and was a contributing factor to my resigning my flair on the topic. My reliability as a historian of the Winter War is only as good as the reliability of my sources, and the unfortunate reality of the situation is that those sources are by and large either extremely dated or lacking academic integrity. As I've found myself locking horns with /u/Holokyn-Kolokyn, Tehruru34, and others, who have often had a firmer basis in more recent, scholarly publications in Finnish or Russian, it's been a fascinating and humbling exercise in re-examining the reliability of the sources I draw upon.
More broadly, it's these kinds of discussions which I feel really can contribute to /r/AskHistorians in a truly wonderful manner. While it's of course embarrassing to make mistakes or indeed discover that the sources upon which you rely are flawed, highlighting these discussions really demonstrates the value of polite, friendly, scholarly disagreement. The real 'winner' from a disagreement like the one I highlight above is the readership. It provides a fascinating insight into scholarly review and puts on display the importance of both primary evidence and of the manner in which we interpret that evidence. It also provides everyone involved with a deeper understanding of the events being discussed - in this case, the naval theatre of the Winter War, and at the risk of sounding overly dramatic, helps us to become better historians by encouraging us to reflect on our own work, research and arguments, as well as the resources we draw upon.
...Or at least, that's what I'll keep telling myself so I can feel better about being wrong on the Internet!
no other answer receives any where near the same amount of upvotes
With regard to your question here, this is due to a critical weakness in Reddit. Early posts get much more attention than later ones. This is why you rarely see multiple posts with the same amount of upvotes.
It's also why we maintain a strict principle of moderation. It helps prevent a short, two-sentence answer from stealing attention from the several-thousand-word, in-depth reply that takes hours to draft.
For anyone who answers questions here, it's enormously frustrating to spend time writing a response to a post, only to have a shorter and much more cursory answer grab all the attention because it was posted 30 minutes before.
I don't know if you'd call it significant but here /u/Jan_van_Bergen and I discuss the different interpretations of the question if Germany was a sovereign state between 45 and 49.
Can't find it now but there was a great discussion a while back about the cause of the USS Maine explosion. Got into very nitty gritty detail, even discussing the combustability of certain types of coal during that period.
one of them keeps recurring and seem to be about 50-50 divided, is: Did Russia's invasion or the atomic bomb compel Japan to surrender in WW II? granted, both sides have good pts. and it almost certainly was a little of both of these; but the sides seem to have equal advocates.