#JanetJacksonAppreciationDay happened because of a confluence of factors... several folks on social media that launched a coordinated campaign. What was awesome was that it really caught on worldwide, as many of us hoped it would.
And of course, a HUGE part of that was a response to the NFL, and their seemingly tone deaf string of decisions. For me, it wasn't directly about Justin Timberlake.
But the other factors were in the air. People see and understand the connections between Janet's career challenges and the current moments of reckoning through the #TimesUp and #MeToo movements. As more and more in the younger generation discover and connect to her music, they too are upset at how she was blacklisted. They see that her career suffered due to factors that she simply had nothing to do with. And in this moment, things like what she endured are no longer acceptable in the entertainment industry. Don't forget that exactly 1 week before the Super Bowl, you had that travesty at the Grammys where Lorde, the only woman nominated for Album Of The Year, was shut out from even being able to perform. Then the President of the The Recording Academy saying the next day that if women want to be respected in the music industry, they need to "step up". In the post SBXXXVIII Fallout, it was Janet that was disinvited from the Grammy Awards, while Justin went, and won that night.
All of these things were connected, and they were contributors to the movement's success.