>By your inflation-factoring-logic a fair regular plan should cost less than $12 and ad plan should be about $6. $9 is +50%

You're misunderstanding my comment. I'm not arguing that price hikes haven't occurred. In fact I specifically acknowledged them. I'm only making the narrow argument that despite implications to the contrary, the ad supported plan today is cheaper than the paid plans. In other words the implication that "we're paying more and still have ads" is false.