It's been an interesting week for considering the impact of slash fanfic on Sherlockiana as a whole.
From an article trying to pin down its rise on Inverse, to a less than positive reaction to discovering a Holmes/Watson romance from John Foster when he wasn't expecting one, to a point in a discussion with a non-Sherlockian pal on Captain America's latest crisis where he admitted not liking the constant slashing of male friends in media because it sexualizes male intimacy. I understand his point and I sympathize with John Foster's issue at not being fully informed of what he had coming in the mail.
Johnlock fan fiction isn't really for us boys, and we really aren't yet sure what women are saying about the male gender with it. (Which varies by individual woman, of course.) We don't always react well to it, especially when presented as the one true vision of Holmes and Watson, despite what anyone wrote prior. (Subtext is the only true reality!) This doesn't mean we're bad people. We're just . . . men.
Whatever that means . . .
The Inverse article presents details from the history of Sherlockiana in a way that might seem to the casual reader that Holmes and Watson slash has been going on as a part of our fandom forever, and the fact that Sherlockiana precedes Star Trek fandom might even mean we were into slash fiction first. As a lifelong Sherlockian and Star Trek fan who was alive when Trek slash began, I can definitely say Trek slash was here waaaaaayyyy before Holmes/Watson. Heck, Starsky and Hutch slash was here waaaaaayyyyy before Holmes/Watson. Why?
Because until recently, Sherlock Holmes and Dr. Watson were always old guys and no one wants to see a lemon party. (Don't google that phrase without preparing yourself for nudity of the wrinkly variety.) Not even most fans of Johnlock. (As evidenced by the non-rise of Mr. Holmes porn. Sure, somebody had to do it once or twice just to do it, but I bet their hearts weren't in it.)
I still have actual print fan fiction from the Jeremy Brett olden days, and it's interesting. It plays up the intimacy and love between Holmes and Watson, turning the Canonical relationship up to eleven, but there is no sex and no kissing. Written for the most part by women, just as today's fanfic, it shows where Sherlock Holmes fanfic will eventually head, being more about relationships than mysteries much of the time, but Sherlockians weren't quite ready to go as sexual as Trekkies just yet in the early 1990s. And back then, gay porn featuring Sherlock Holmes was still actually that -- gay porn. By men for men.
I'm sure someone can cite a story or two they saw that goes against the statements above, but by and large, Sherlock Holmes fandom did not come to the slash party until Cumberbatch and Freeman and the tremendous influx of female fans. (Recall that America's core of Sherlockiana, the Baker Street Irregulars, didn't even allow women at its dinners until the 1990s.) Gender plays such a large role in looking at this particular part of fan culture that implying certain things have always been so starts to verge on history denial.
Star Trek fan culture is a good place to look to see where Sherlockiana might be headed, oddly enough. While media, like old Saturday Night Live skits tended to portray Trekkies as geeky males back in the 1980s, attending cons showed you a different picture -- that the fandom was predominantly female. And that slash was a big part of that. But somehow, Star Trek being all about a positive future with philosophies like IDIC (Infinite Diversity in Infinite Combinations) folks seemed pretty much cool with that. The neighbors did what the neighbors did, but you were all still happy to be living on Trek street.
And we'll get there eventually, I think, unless we see some odd retro rise of male-only enclaves dedicated to barricading themselves against our expanding fan culture. (Or female-only enclaves devoted to the mindset that Holmes/Watson man-love is the only true Canon.) These things just take time.
And fortunately, as evidenced by a century and a quarter of Sherlock's popularity, we have time.