They're all pop. I say this as a long-time DP fan and knowing that I'll get murdered for it, but if there's a commonality it's that they sell huge volumes to young people.
This is how I see it:
Oh we see you like two artists that are not widely popular amoungst teenage girls, here, we recommend a boy band widely popular amoungst teenage girls!
I just don't see how that works, even if they're in a similar genre
Plus who knows what kind of shady deals are going on behind the scenes? It's a whole new marketplace and publishers are still trying to find their feet.
Oh we see you like two artists that are not widely popular amoungst teenage girls, here, we recommend a boy band widely popular amoungst teenage girls!
I just don't see how that works, even if they're in a similar genre