When we are young... we often experience things in the present with a nostalgia-in-advance, but we seldom guess what we will truly prize years from now.
Being up on something is a way of dismissing it. To espouse any point of view is a danger - it might leave us stuck with last year's cause. Prized for their novelty alone, ideas, gimmicks, trends become equivalent, interchangeable.
The culmination of a long struggle was 2013, which could clearly be labeled the Year of the Gay. State after state had legalized gay marriage, despite intense opposition from the religious right.