Hm I don't know, I will be 23 this year so I practically only really experienced 2 decades.

the most important events this decade probably were Brexit, the election of Donald Trump and the refugee crisis in 15/16. Important long term developments were the rise of far right parties and the strong increase of momentum for the environment movement.

I was born in 1981. I have a very clear image in my mind of the identities of the 80s and 90s (and the 70s and earlier decades, I just didn't experience them). The 00s and 10s, not so much. They both blend and have no real standout features (music, clothing trends, etc.) to me.

Yes, to me the 90's were the decade of The Simpsons and X-Files, the 00's was the decade of 24 and LOST and 10's is the decade of Game of Thrones

This past decade is the decade of social media. It wasn't terribly prevalent before this decade, and I think people are getting somewhat sick of it and its influence.

Decade of everyone wants to sell you streaming services instead of classic stuff

The decade of representation.

I still prefer to think in my old decade.

To me, this decade.... does not seem to have an identity at all... Really

Having lived half of the 70´s, the 80´s, the 90´s and the 2000´s.... I have the feeling that that´s nothing in particular in this decade that defines it, be it about fashion or design or music or entertainment..... It´s so weird. I can easily pinpoint some highlights that defined those decades, some looks and sounds, those decades all seem very different and very recognizable, but this decade seems kind of confusing. Perhaps because popularity today, wherever its focus may be, vanishes vary fast in this age of always-available internet.

Only two things comes to my mind when thinking about the identity of this decade: the smartphone addiction and the progressive/political correctness madness dominating social media services. In the 2000´s social media was fun and entertaining, but in this decade.... everything is so boring, over-politicizing, extremely polarized, not fun and not productive at all. 

Still, those are not "things" that, in my view, would define the looks, the feels, the sounds and the identity of this decade.