Anyone who would say that hasn't been paying attention. Not only had innovation on Reader slowed to a halt, but Google was also working on and prioritizing products that competed with it (G+). There is a reason why Feedly was able to move so quickly on replacing the Google Reader API, they were anticipating the shutdown of Reader for a while.
How so? RSS is definitely niche (especially when compared to those three), and I don't see how they would be making money off it, except via ads - turning off AdBlock, I don't see any.