Why streamings are so important? Check this two photos from IFPI Switzerland. They speak for itself:
Here is what Spotify says:
We take this sentence from this page -> Link
"You can increase your chances of making it onto all these playlist types by continuing to grow your fanbase. Check out our promo guide for tips"
I think this sentence means: The more people listen to your music the more interesting you are for Spotify and the bigger the chances are, that you will make it on a official spotify playlist