As I said earlier in this thread, the culture and mentality truly started around 2011 with Occupy Wall Street and gradually built up before reaching full force in 2014-2015 with Gamergate and Black Lives Matter (as well as the legalization of gay marriage nationally resulting in the troons essentially hijacking the LGBT movement) with 2016-2017 seeing the SJW's go into overdrive with the rise of Donald Trump and the fall of Harvey Weinstein making the SJW Left more aggressive and authoritarian than ever.
2017 is the year that "Current Year" arguably reached critical mass with Antifa becoming a household name and #MeToo becoming the biggest witch hunt in American history since either McCarthyism or the Satanic Panic.
But I also sort of realize that "Current Year" could not have happened or at least not gotten as bad as it currently is without the infrastructure of social media and the "new" internet culture that came about in the late 2000's (as the meme goes, 2007 was the year everything went to shit)
Basically, 2007-2009 was an era of massive change. The oldest of the Millennials were finally entering adulthood in mass while the youngest of the Millennials were in high school and entering their teenage rebellion phase. A person's teens and early twenties are often a very important time in the emotional and psychological development of a person, and a lot of SJW's are also Millennials.
The Millennials were the children of the mid-to-late 1980's and early-to-mid 1990's, and would have spent most of their childhoods during the relatively centrist Clinton years and the very conservative Bush years, the latter of which gave us 9/11, The Patriot Act (which allowed the current surveillance state to really take off unimpeded), two failed and very unpopular wars (one of which is still ongoing), and The Great Recession. Also, the Religious Right was still a powerhouse in the 1980's and 1990's, and while not as powerful in their heyday, were still very much culturally and politically relevant in the 2000's, particularly during Bush's first term. So this is basically the kind of world that most Millennials grew up in prior to entering high school and college for the first time.
During the 2000's, the Internet rapidly goes from something largely the purview of nerds and tech people to a facet of everyday life for even the most normie of people, with the era of 2007-2009 being the years of the most sweeping changes in terms of normalizing internet culture in the mainstream.
In 2000, the saying was that there were no girls on the internet while by 2009 even your seventy-eight year old grandmother has a Facebook and posts cringe-inducing image macros on it regularly.
So, by this time nearly everyone has access to the internet and social media is becoming the "in" thing even among the most mainstream of the so-called normies.
What else happened in the era of 2007-2009 when all these future SJW's were either in high school or just starting college and social media was born? Well, there was the Great Recession of 2008-2009, the Christian Right basically losing all credibility and relevancy even among most Republicans, and the rise of Barack Obama.
Obama was a largely centrist politician whose policies and initial platform were even more moderate than Clinton's platform in the 1990's.
In terms of actual hard policies, Obama was pretty much a direct continuation of Bush-era policies but with a thin veneer of empty progressive rhetoric. Combine that with the fact that he was black and knew how to appeal to young people at the time, as well as the Republicans finding themselves less able to rely on winning by pandering to the fading Religious Right and you had the ultimate false hope.
Obama turned out to be another empty suit and did not bring all these leftist reforms that so many of these young Millennials who grew up under Bush hoped he would.
Obama didn't even attempt to close Guantanamo Bay and that was one of the few things he actually said he was going to do.
So by 2011-2012, you have the older Millennials finding themselves with mostly worthless college degrees and also up to their eyeballs in student debt and the younger Millennials are now graduating high school with no real hope for a future (the recession was over by 2011, but the economy wasn't really visibly improving on the street levels until around 2013-2014 at the absolute earliest) and you take this sense of anger and despair, combine it with a leftist bent due to growing up under Dubya, and this leads to Occupy Wall Street, which is where the SJW's of today as a large movement truly begin.
Occupy fails to achieve its goals in nearly every way imaginable, but thanks to social media and the new mainstream internet culture, it was able to become a nationwide phenomenon and not be confined to the major cities. I live in what can be described as a smaller regional city at best and even we had major Occupy protests in 2011 and 2012.
So now these Millennials who formed Occupy feel emboldened and more committed, feeling that maybe they can get it right if they try harder and become even more dedicated in their leftist online activism and slacktivism. Also, around this time even the Republican leadership realizes that the Religious Right is basically irrelevant following Obama's re-election in 2012. Why is this important?
The fact that the Religious Right, once the dominant force in moral authoritarianism for most of the 1980's and 1990's (and even into the 2000's) was essentially dead and unable to do anything meant that there was no longer a common enemy for the SJW's to rail against. So the Millennial Left essentially became the 2010's equivalent of the Religious Right and began attacking everything they did not agree with, becoming the same kind of monster that they hated when they were kids and teens in Bush-era America.
TL;DR Current Year began in 2011-2012 but couldn't have become what it is now if 2008-2009 hadn't happened.