Activism is absolutely more than pointing out the negative and calling it a day, which seems to be the real point of Obama's statement, moreso than "don't go woke".
At some point you do have to be the one to step up and be the change you want to see if you're going to consider yourself active, or you're no different than the cranks who just complain on social media all day of how the world is going to shit, the same people who have been doing so for decades and more in various forums and media.
This is not to say DON'T point out injustice when it happens.
In fact now that I've spooled through the majority of closing comments at that summit, the general tone seems to be "Yes, you will actually have to wake up, get up, get out there, because no one's going to do it for you."
And the way Obama opened up his statement is to reinforce that most of the leaders of the Civil Rights Movement "were your age" (referencing the college-age students in the room).