I've been in fandom since 2001, definitely before 2004, and if anything, I've seen a lot more of people openly posting chan/smut/kink/etc. in recent years. Back in the days of personal webpages (many of which were still around when I was a newbie fan), I remember having to click past numerous warnings -- and possibly submit an age statement -- just to get to garden-variety slash.
Warnings and ratings have also been around throughout my fannish experience (along with pairing labels, which were so common in GW and Weiss yaoi and on Fiction Alley that I assumed that not including them constituted leaving out a vital part of a fic, comparable to forgetting to give it a title). I'd always assumed that they were assigned and included as a courtesy to other fans (especially other fans reading on family or public computers, who might not want someone looking over their shoulders and seeing a screen full of explicit sex), rather than as some kind of attempt to "clean fandom up." Clearly labeling for content is a far cry from hiding it or being ashamed of it.
If anything, I've generally found that ratings and labels make porn and darkfic easier to find.
no subject
Warnings and ratings have also been around throughout my fannish experience (along with pairing labels, which were so common in GW and Weiss yaoi and on Fiction Alley that I assumed that not including them constituted leaving out a vital part of a fic, comparable to forgetting to give it a title). I'd always assumed that they were assigned and included as a courtesy to other fans (especially other fans reading on family or public computers, who might not want someone looking over their shoulders and seeing a screen full of explicit sex), rather than as some kind of attempt to "clean fandom up." Clearly labeling for content is a far cry from hiding it or being ashamed of it.
If anything, I've generally found that ratings and labels make porn and darkfic easier to find.