That seems disingenuous towards their (paying) users. I guess their never promised "music neutrality" but still ...
Funny as they also also announced price raises last week, talk about winning on both ends.
Back in the day that was called payola. The producers who can afford a reduced rate (reduced from the already miniscule payments producers get) can get inserted into the rotation more often.
So what you're hearing as a user isn't what's more popular, or chosen for some kind of artistic value; you're hearing what producers have paid for.