So far I think "Uptown Funk", "Blinding Lights", and "Old Town Road". That doesn't mean I love those songs. It means I think they answer the question. I know you may love "Irony x3" by Zigbones. But they ain't it.
Edit: I'm sorry for the poorly worded question. I think it's autism related, but I don't see possibilities or alternative understandings easily, and when I wrote "decade" I thought 10 years and that was it.
Of course anyone answering from the perspective of 2010-2020 was making a perfectly reasonable and rational answer and I was very dismissive. I'm really sorry for that.
I think the last decade has about 10-15 classic songs (e.g. rolling in the deep, get lucky etc), but that's nothing compared to the '80s, where the classic songs measure upwards to 700. There is cultural stagnation in the last 10 years, particularly after the death of the indie music as a vehicle for innovation (i.e. the Pitchfork golden era of 2008 to 2012 where indies became the next hot thing). I could say the same for movies. For me, the highest point of cultural significance, was 1984 (more precisely, the last 3 months of 1983, the whole of 1984, and the first 6 months of 1985, ending with the Live Aid). That's the most classic, highest point IMHO for both music and movies, where pretty much what was getting released, was becoming an instant classic. Basically, most of it was good, rather than bad with exceptions. There are a few articles online talking about the same thing as I did here, and there's also a couple of books, all recognizing 1984 as THE year of culture. Today, we're running on fumes.